Inositol is a non-essential nutrient and natural sugar present within phospholipids of cell membranes, plasma lipoproteins, and the nuclei. Chemically, there are 9 subtypes of inositol each with distinctive stereoisomers, the most common of which is known as “myo-inositol.” Within the human body, myo-inositol is synthesized from glucose and accounts for 95% of total free inositol content; its concentrations are highest within spinal fluid.
Since the discovery of inositol in 1849, researchers have elucidated its functional importance within the body. Principally, inositol promotes functioning of signaling molecules and secondary messengers. Moreover, inositol plays an integral role in facilitating various biochemical processes including: fat breakdown, gene expression, insulin signal transduction, intracellular calcium (Ca2+) modulation, and nerve cell signaling.
Despite inositol’s classification as a non-essential nutrient, research suggests that it is likely conducive to general health and well-being. When taken in large doses, inositol may be an effective treatment for conditions such as: anxiety disorders, depression, eating disorders, hyponatremia, metabolic syndrome, and polycystic ovary syndrome (PCOS). Although high-dose inositol supplementation may attenuate symptoms of a medical condition, many individuals experience unwanted side effects.
Inositol Side Effects & Adverse Reactions (List)
Surprising to many is the fact that there aren’t usually any significant unwanted side effects associated with inositol. Side effects from inositol may be unlikely due to the fact that the body is well-adapted to its presence and involvement in biochemical processes. That said, the most common side effects reported by inositol users include: dizziness, headaches, gastrointestinal distress, and diarrhea (or loose stools) at high doses.
Appetite reduction: A side effect that many inositol users perceive as favorable is a reduced appetite. You may notice that after taking inositol for a week or two that you’re eating less than usual or just not as hungry as you were pre-inositol. It is unclear as to how inositol reduces appetite, but appetite reduction likely stems from a complex interplay of neurophysiologic changes as induced by inositol.
You may notice that it is easier to resist food cravings and urges to overeat. Part of this may be due to the fact that inositol indirectly modulates neurotransmission, insulin, and blood glucose. If you’re already skinny and/or underweight, you should beware of inositol’s propensity to decrease appetite in a subset of users.
Bloating: A less common side effect reported by some inositol users is bloating. When taking inositol, you may feel as if your stomach is constantly full of fluid and/or gas, which is often mildly uncomfortable and perhaps irritating. If you suspect that the bloating is caused by inositol, you may want to scale back on the dosing as lower doses may ameliorate the bloat. Realize that bloating may also be most common when you first start taking inositol and that it may subside over a longer term of administration.
Blood sugar reduction: Studies have shown that inositol is capable of reducing blood sugar and fasting insulin levels, all while improving insulin sensitivity. Though a reduction in blood glucose is usually perceived as therapeutic in the general population, this side effect may be unwanted among individuals with diabetes. If you have diabetes, particularly Type 1, it is necessary to be cognizant of hypoglycemia as a potential side effect associated with inositol supplementation. The greater the dosage of inositol you’re taking, the more significant it is likely to reduce a user’s blood sugar.
Brain fog: Although many people derive therapeutic benefit from using inositol for anxiety disorders, sometimes it’s a catch-22 in that an anxiety reduction may lead to “brain fog.” If you feel spaced-out while taking inositol and/or like a brain-dead drone, you’re not alone. In some cases, the brain fog may gradually subside after a few weeks of regular inositol supplementation as your body adapts to high-dose administration.
However, extreme brain fog may also be a sign that you’re taking too much inositol. Excess inositol may dampen your conscious awareness by bolstering a relaxation-response, possibly via increasing serotonin signaling and/or decreasing beta waves. Realize that to avoid brain fog while taking inositol, it may be necessary to reduce your dosage. Some users have reported that brain fog from inositol is most evident in the early mornings.
Cognitive impairment: Another side effect that inositol users report is that of cognitive impairment. You may notice a significant decline in cognitive performance after you start taking inositol compared to pre-treatment. In some cases, a decline in cognitive performance may be a result of mechanisms that contribute to inositol’s anxiolytic effects.
An increased neurophysiologic relaxation response may impair your ability to concentrate, encode memories, and/or learn new material. If it seems as if your productivity and ability to complete cognitively-demanding tasks (e.g. reading, writing, planning, problem solving) at work or school has declined after taking inositol, it may be more than a coincidence. Those experiencing cognitive impairment as a result of inositol may benefit from a dosage decrease.
To accurately gauge whether your cognitive performance is affected by inositol supplementation, you’ll want to administer a reputable cognitive battery pre-inositol and during treatment. By comparing your cognitive testing scores, you’ll be able to objectively test for differences. That said, if you subjectively notice that after inositol, you cannot think as critically, quickly, or deeply – you may want to discontinue.
Diarrhea: A side effect reported among inositol users, especially those taking high doses, is diarrhea or loose stools. If you catch yourself running to the bathroom frequently throughout the day with “disaster pants,” and you just started taking inositol, the inositol may be to blame. In addition to diarrhea, inositol users report stomach cramping and aches, gastrointestinal distress, and increased flatulence.
An obvious strategy for decreasing likelihood of diarrhea while taking inositol is to start with a low dose. Generally, those that experience diarrhea as a side effect are taking higher-than-average supplemental doses of inositol. In some cases, diarrhea may be transient and subside after a few weeks of inositol usage. In other cases, a user may need to discontinue and/or concomitantly administer an antidiarrheal such as Imodium.
Dizziness: A ubiquitously reported side effect for nearly every supplement and/or drug is dizziness. It is unclear as to whether inositol actually causes dizziness or whether dizziness experienced while taking inositol is a result of other factors (e.g. psychosomatic effects). If when you take inositol you feel dizzy, yet when you don’t take it, you don’t feel any dizziness – it’s likely that inositol is the cause.
The dizziness may be temporary (as a result of an adjustment to higher levels of inositol), but could also be from changes in blood pressure, circulation, and vasodilation. As a result, those who report dizziness often experience mild lightheadedness. Dizziness may subside with continued treatment, but if it doesn’t, consider reducing your dosage or discontinuing inositol altogether.
Excessive sleep: One notable benefit of inositol is that it can improve sleep quality and duration, particularly among those with anxiety and/or stress-induced sleep dysfunction. However, a drawback associated with inositol supplementation is that it may cause some individuals to sleep longer than usual and/or require extra sleep. If prior to taking inositol you only needed 8 hours of sleep to function, yet after taking inositol you constantly slept for abnormally long durations (e.g. 10+ hours) – this may be viewed as a problematic side effect.
Many users reporting unwanted excess sleep from inositol have found that a simple dosage reduction corrects the problem. You may want to decrease your dose or administer inositol at a different time of day than usual to determine whether it attenuates the need for excess sleep. Obviously if all you want to do is sleep when taking inositol (e.g. you feel fatigued and/or exhibit hypersomnia) – it’s probably not a good supplement for your neurophysiology.
Fatigue: If you have a history of fatigue and struggle with low energy, inositol may exacerbate these symptoms. At low to moderate doses, inositol isn’t likely to completely sap your energy and zest for life. However, some have reported that when they take high doses, they end up feeling energetically drained and more fatigued than usual.
While a decrease in overall energy may be of benefit to someone who’s naturally high-strung with anxiety and/or stress, it may be an unwelcome side effect for a person who struggles with low energy. Keep in mind that reducing inositol intake can often ameliorate and/or completely reverse fatigue induced by high doses. Also realize that fatigue or a temporary dip in energy may be transient and cease as the body adapts to the exogenously administered inositol.
Flatulence: It is common to notice gastrointestinal distress when you start taking inositol, especially at high doses. This gastrointestinal distress may provoke stomach aches, diarrhea, and unpleasantly enough, moderate flatulence. If you feel as if the only thing inositol is good for is to generate stomach gas or the flatulence is excessive (to the extent of embarrassment), you may want to decrease your dosage. In some cases, initial flatulence experienced from inositol subsides with continued supplementation and/or dosing adjustments.
Gastrointestinal distress: Inositol may cause gastrointestinal distress in a subset of users, characterized by stomach aches/cramps, flatulence, nausea, and perhaps for the extremely unlucky, diarrhea. In some cases, this may be a sign that your body is unable to tolerate the extremely high dose of inositol that you’re taking. In other cases, gastrointestinal distress may be a result of a poor-quality inositol brand, concomitant ingredients in your supplement, or even an interaction with another supplement (or drug) that you’re taking.
To decrease likelihood of GI issues while taking inositol, consider starting with a low dose and titrating upwards at a fairly slow rate. If you experience GI issues, it may be that you’ve increased your dosage at too quick of a rate for your body to accommodate. Realize that in many cases, gastrointestinal issues are transient and diminish with continued inositol usage. If you’re on a dose of inositol that’s effective in treating neuropsychiatric symptoms, yet it’s causing GI distress – consider an over-the-counter agent to combat this distress.
Grogginess: Many people end up experiencing extreme grogginess when they first start taking inositol. The grogginess may subside with continued usage, but to avoid grogginess in the first place, start by taking just a low dose and working your way up to a comfortable dose. Most low-dose users do not report grogginess, yet those who’ve taken too much inositol may wake up after a full night’s sleep feeling mentally lethargic and groggy with brain fog.
It is possible to consider that grogginess may be related to modulation in the neurotransmission of monoamines, overactivation of the parasympathetic pathways, decreased sympathetic activation, or possibly from getting too much sleep (which can also occur among inositol users). Commonsense remedies such as caffeine or even mitochondrial enhancers may be helpful in combatting inositol-induced grogginess. If you experience grogginess from inositol, it is likely to be most prominent during the morning.
Headaches: One of the most commonly reported inositol side effects is headaches. Usually the headaches stemming from inositol supplementation are of mild to moderate severity. Although the cause of these headaches isn’t well known, it may be due to the fact that a reaction akin to a glucose spike (sugar rush) is triggered by inositol; it is synthesized from glucose.
Headaches may also be a result of excess nerve cell signaling and/or altered neurotransmitter system functioning (e.g. acetylcholine, serotonin, etc.). Since inositol tends to induce an anxiolytic effect, can lower blood pressure, and improves circulation – headaches may occur as a result of excess vasodilation. That said, it is uncommon for inositol users to report full-blown migraines.
Realize that headaches may subside as a person’s body adapts to the presence of extra inositol. However, a subset of users who didn’t initially experience headaches when starting inositol, report the emergence of headaches after an extended term of treatment. In some cases, it may be necessary to decrease inositol dosing, switch brands, or simply stop using it for awhile to avoid these headaches.
Insomnia: It’s no secret that many people have success in treating their insomnia naturally with inositol supplementation. However, in some cases, users may notice that preexisting insomnia is exacerbated after they take inositol. In other cases, even those with no prior history of insomnia notice that they’re unable to fall asleep in a timely manner after taking inositol.
Although insomnia is a counterintuitive reaction to inositol, it is one that has been reported. If you’re experiencing insomnia while taking inositol, it may be necessary to adjust the dosage, time of day that you take it, and/or cease usage for the sake of your sleep. The exact causes of inositol-induced insomnia remain unknown, but could be a result of altered nerve cell signaling and altered neurochemical activity.
Itching: Although most people aren’t allergic to inositol supplementation, it is necessary to review the full list of ingredients within your particular inositol supplement to ensure that there aren’t any sketchy additives that may prompt an allergic reaction. You may also want to review your inositol supplier as to minimize likelihood of batch contamination. If your skin becomes itchier after taking inositol, it may stem from an increase in histamine production.
One strategy that may prove efficacious is to simply decrease the inositol dosage, then reassess the itching a few days later. If the itching subsides, it may be that you were simply taking too high of a dose for your body to handle. In most cases, itching from inositol is of mild severity and may be accompanied by a perceived skin rash and/or reddening.
Libido reduction: A common reason people stop taking SSRIs is their propensity to decrease libido. Although inositol isn’t known to cause severe sexual dysfunction, inability to orgasm, or complete lack of sex drive – a subset of users have reported decreases in libido. If you have a higher-than-average libido prior to taking inositol, this side effect may not be perceived as problematic.
A drop in libido from taking inositol may be due to its upregulation of the parasympathetic nervous system and/or enhanced signaling of calming neurotransmitters (e.g. serotonin). It could also be due to its ability to modulate levels of hormones. If you take inositol for awhile (e.g. several weeks or months) and libido remains subdued, it may be worth altering the dose, augmenting with a libido enhancer, or simply ceasing usage.
Lightheadedness: Don’t be surprised if when you start taking inositol you experience lightheadedness, mild dizziness, and perceived minor deficits in balance and coordination. Feeling lightheaded is a common side effect that inositol users report and may be nothing more than adaptive response as the body adjusts itself to an upregulation in inositol concentrations. It could also be that lightheadedness is caused by changes in blood circulation and/or a vasodilatory response generated by the inositol.
Assuming the inositol is increasing activation of the parasympathetic nervous system, an individual may exhibit physical relaxation and decreases in blood pressure – each of which could also contribute to lightheadedness. Certain users have noted comorbid dizziness simultaneously with the lightheadedness which is slightly unpleasant. Should lightheadedness fail to subside with continued inositol supplementation, you may want to: reduce dosage, discontinue, and talk to your doctor.
Low testosterone: There is evidence to suggest that inositol supplementation (e.g. myo-inositol) can decrease testosterone levels in women taking it for PCOS (Polycystic Ovary Syndrome). PCOS is a condition in which the ovaries produce excess testosterone, therefore, reducing levels is a therapeutic goal for those taking inositol. It is unclear as to whether inositol may reduce testosterone levels among women without PCOS and/or men supplementing with inositol.
Some speculate that it exhibits a balancing affect, thereby correcting hormonal abnormalities. Others hypothesize that it may actually reduce testosterone in both men and women and speculate that this could be problematic. If you have a history of low testosterone and/or are concerned about hormonal imbalances as a result of inositol, it may be best to monitor them regularly every several weeks and/or months of inositol supplementation.
Mood swings: For a majority of individuals, inositol increases calmness, enhances positive emotion, and decreases propensity of mood swings. However, among select individuals, particularly those diagnosed with bipolar disorder, schizophrenia, or even certain types of depression –inositol causes unwanted mood swings. If you notice that after taking inositol, you experience a worsening of depression, negative emotion, or fluctuation in your emotional state – it may be worth discontinuing.
Some individuals may notice that mood swings occur solely during the first couple weeks of inositol supplementation and fade with continued administration. In these cases, the body simply may have needed some time to adapt to the upregulated level of circulating inositol – causing mood swings until it fully adjusted. Should you experience mood swings, you may want to modify dosing to determine whether a reduction (or increase) minimizes mood fluctuation.
Nausea: A common side effect experienced by those supplementing with inositol is nausea. It is unclear as to what causes this nausea, but some speculate that it’s a byproduct of digestive changes and/or gastrointestinal distress. The nausea may also be a signal from the body letting you know that it has received too much inositol and is having a difficult time accommodating the excess, non-homeostatic level.
It is also possible that some users may experience nausea resulting from a psychosomatic effect. Nausea is may be most common among those ingesting extremely high-doses of inositol and/or inositol interacting with another drug or supplement that a user is taking. Many report diminished nausea with continued inositol supplementation as the body adapts to its presence. Only in rare cases is nausea extreme enough as to induce vomiting.
Restlessness: An uncommon side effect stemming from inositol supplementation is restlessness accompanied by agitation. Restlessness is considered a counterintuitive side effect due to the fact that most users find inositol to bolster feelings of calmness (the opposite of restlessness). If you notice that you want to constantly move and/or exhibit increases in agitation after taking inositol, you may want to lower your dose or cease administration.
It is unclear exactly what causes the restlessness, but it could be due to early alterations in nerve cell signaling and/or neurotransmitter systems. Those that experience restlessness while taking inositol are more likely to have a preexisting psychiatric condition and/or be taking other meds (or supplements) that could provoke restlessness or interact with inositol to cause restlessness.
Skin rash, redness, flushing: A small percentage of inositol users notice reddening of the skin, a skin rash, and/or skin flushing as a side effect. Skin issues while taking inositol may occur as a result of increases in histamine levels. Elevated histamine levels are understood to provoke allergy-like reactions such as skin flushing, reddening, and itching.
Some individuals report that their skin feels warm and/or extra sensitive after they began supplementing with inositol. If you’re experiencing any disconcerting skin reaction while taking inositol, it is recommended to seek medical attention to rule out a more serious cause. In most cases, the skin rashes associated with inositol are mild.
Certain users may notice that skin rashes subside with continued inositol usage, while others notice a worsening of the skin reaction. To minimize likelihood of a skin rash, users may want to take a lower inositol dosage. Also beware of the fact that the rash could be caused by an additional ingredient within your particular inositol formulation to which you’re allergic.
Sleep disturbances: While many inositol users experience deeper, more restful sleep after supplementation, others notice disturbances in sleep. A subset of inositol users report an increase in the number of times they wake up during the middle of the night. Frequent waking throughout the night may be caused by alterations in the transitions between various sleep stages or changes to sleep architecture as induced by inositol.
Some users may report weird (possibly nightmarish) dreams that jolt them out of a deep slumber and suspect that they may be related to the inositol. Keep in mind that dosing of inositol likely plays a role in whether you experience sleep disturbances, as well as the time of day that you take it. You could simply reduce your dosage and/or take inositol at a different time of day to determine whether these sleep disturbances can be mitigated.
Stomach aches: A common sign of increased gastrointestinal distress is a stomach ache. If after taking inositol you notice frequent stomach aches and cramps, it may be a sign that you’ve ingested too much at once for your body to utilize. To avoid stomach aches while taking inositol, you may want to divide your dose up into several smaller doses that can be administered at differing time intervals throughout the day (e.g. morning, noon, night).
It may be of benefit for some individuals to take inositol at lower doses to determine whether a dosage reduction decreases stomach aches. Another possible mitigation strategy is to take inositol after a large meal and/or with food. If you are deriving therapeutic benefit from inositol and do not wish to alter your dose, realize that certain over-the-counter medications may offset the stomach aches from inositol that you experience.
Sweating: Certain inositol users may notice that while supplementing, they sweat more than usual. It isn’t known as to what causes increased perspiration, but this is a common side effect associated with most drugs and supplements. If the sweating is extreme and/or fails to subside with continued inositol administration, it should be considered wise to consult a medical professional.
For some, the sweating may be most profound at night, yet others may notice increased sweating throughout the day. This sweat may be accompanied by perceived warmth or slightly increased body temperature. Because sweating can be induced by many things such as: warm temperatures, exercise, other medications, etc. – it’s usually difficult to isolate inositol as the causative agent.
Tiredness: You may feel exceptionally tired all the time when taking inositol, some users have this reaction. The tiredness may stem from increased parasympathetic activation and a heightened anxiolytic effect without adequate stimulation. For this reason, it may be necessary to ingest a lower amount of inositol as to avoid dampening the body’s sympathetic pathways. Realize that for some users, the tiredness is temporary and/or related to changes in sleep (or circadian rhythm) as induced by inositol.
Weight loss: You may take inositol for several weeks or months and notice that you’ve lost weight. Losing weight is often considered an advantageous side effect for many overweight users. However, those that are lightweight, underweight, and/or are trying to gain weight – may dislike this side effect.
It is unclear as to what mechanisms associated with inositol contribute to weight loss. It’s likely an interplay of mechanisms involving: nerve signaling changes, blood glucose reductions, improved insulin sensitivity, hormone alterations, and accelerated fat transport. Weight loss while taking inositol may result from: a faster metabolism, improved sleep, decreased stress, increased satiety, and reduced appetite.
In most cases, weight loss while taking inositol is non-significant and/or transient. In other words, users are likely to lose only a modest amount of weight. With continued inositol usage, it may be possible to gain back some of the weight that was lost in early weeks of administration.
Weird dreams: Inositol is thought to alter neurotransmitter systems of acetylcholine, dopamine, norepinephrine, and serotonin. It is the alterations in serotonergic systems that are believed to facilitate an antidepressant and anxiolytic response in high-dose users. Modulation in signaling of neurotransmitters may lead some users to report “weird dreams.”
Although some may be entertained by the dreams that occur while taking inositol, others may dislike the intense and/or vivid imagery that accompanies these dreams. Some users have reported that after taking inositol, they experienced nightmares and/or regular bad dreams. While most people can cope with the occasional bad dream, if bad dreams occur on a nightly basis from inositol – it may be worth adjusting the dosage, time of day you take it, or simply discontinuing.
Note: It should be noted that not everyone will experience all of the aforestated inositol side effects. In fact, some users may not experience any side effects (or at least noticeable ones) while taking inositol. If you have any additional questions about side effects of inositol, consult a medical professional.
Variables that may influence Inositol side effects
Not everyone taking inositol as a dietary supplement will experience the same side effects. One inositol user may report diarrhea and dizziness, another may feel fatigued and sleep excessively, while a third may experience minor weight loss. The difference in total number of side effects, their respective severities, and the specific side effects experienced – are subject to individual variation. Variables such as inositol dosage, inositol subtype, term of administration, co-ingested substances, and inositol source/brand likely influence side effect severity.
Dosage (Low vs. High)
Some inositol users find supplementing with a low dose (e.g. under 1 gram) alleviates their medical symptoms, while others require much higher doses for symptomatic relief. In most cases, side effects from inositol become most noticeable among those taking high doses. Examples of side effects that are most likely to occur at high doses include: diarrhea, gastrointestinal distress, and stomach aches.
Although the body is well adapted to utilize inositol, high doses are thought to alter homeostatic neurophysiologic processes. In other words, the high doses are exerting a greater change in a user’s neurophysiology from homeostatic baseline, thereby leading to side effects. Perhaps some users are incapable of tolerating and/or adjusting to high doses.
Many low-dose inositol users note that they don’t experience any side effects – or at least any that they can definitively chalk up to the inositol. However, those taking upwards of several grams of inositol per day usually report looser stools, changes in sleep, and changes in energy. Since dosing of inositol can affect the occurrence of side effects, taking the lowest dose capable of managing symptoms should be advised.
Duration of administration
The total duration over which you’ve consistently supplemented with inositol may determine whether you experience side effects. Individuals that have taken inositol for a short-term (e.g. several days) may not have adjusted to the neurophysiologic effects of heightened inositol concentrations. However, with continued inositol usage, the body may adapt to inositol and side effects that occurred over a short-term may subside.
In other cases, inositol users may not notice any short-term side effects, but may experience side effects after a moderate and/or longer-term of treatment. Side effects that occur over a longer-term of inositol supplementation may be due to dosage increases and/or cumulative alterations in physiologic processes (e.g. cellular signaling, neurotransmitter systems, etc.) as induced by inositol. Generally, long-term inositol users have optimized their dosages, adapted to the enhanced inositol levels, and don’t experience many side effects – if they had experienced significant side effects, they would’ve likely discontinued inositol before a “long-term.”
Those taking inositol supplements may perceive the inositol as causing their side effects, when in reality, it could be a result of co-administered substances. If you’re taking an entire stack of supplements and/or pharmaceutical drug(s) with inositol, it may be necessary to consider that the other substance(s) are contributing to your side effects. Individuals that started taking inositol on the same day as a certain supplement or drug cannot be certain that the inositol was causing their side effects, yet may blame the inositol rather than considering the other co-ingested agent.
Unless you’re taking standalone inositol (with no other supplements or drugs), it is very difficult elucidate whether inositol is the chief causative culprit of your side effects. You should also realize that it is possible that inositol alters the pharmacokinetics and/or pharmacodynamics of another substance that you administer, possibly leading to an interaction. Though inositol is thought to have a low propensity for contraindications, the potential for interactions to cause side effects should be considered.
There are 9 distinct stereoisomers of inositol, but the most common is myo-inositol. That said, most individuals supplementing with inositol are taking either: d-chiro-inositol, myo-inositol, or a blend of “d-chiro” plus “myo.” A rare subset of inositol users may also be taking the synthetic inositol analogue known as epi-inositol.
Although whether side effects are more likely to occur with one particular format of inositol isn’t elucidated due to lack of comparative studies, it should be considered as a possibility – especially in the case of the synthetic, unnatural epi-inositol. If you’re experiencing side effects on one particular type of inositol, it may be worth trying another to determine whether they diminish and/or subside.
Inositol source + additives
The particular source and brand of the inositol supplement that you take may determine whether you’re likely to experience side effects. Certain manufacturers have poor standards for quality control and may sell inositol products laden with additives, or worse – contaminants. Though contaminants are unlikely, they should be considered whenever purchasing inositol from an unknown retailer or a manufacturer with a suboptimal reputation.
Obviously if your inositol batch is somehow contaminated and/or compromised, side effects are very likely to occur. To avoid this problem, simply purchase inositol from a reputable vendor that sells a quality product. In addition to purchasing inositol from a quality source, you’ll want to ensure that your inositol is devoid of additives.
Some additives such as choline may augment the efficacy of inositol, but until you know how you react to inositol first as a standalone agent, avoidance of additives is recommended. Why should you avoid additives? Because you may exhibit an adverse reaction as a result of the additive within your inositol, yet mistakenly assume that inositol was causing the effect.
That said, it may be necessary to consider that adjunctive inositol additives may enhance bioavailability and/or mitigate unwanted side effects. In select cases, some may find that they actually react better (e.g. have less side effects) to inositol with certain additives. As a general rule of thumb, be cognizant of your inositol sourcing as well as potential additives when contemplating side effects.
Inositol: Do the benefits outweigh the side effects?
Whenever supplementing with inositol, it is helpful to regularly to reflect upon whether the therapeutic benefits outweigh the side effects (or financial costs). If you’ve been taking high-doses of inositol each day for months, yet don’t experience any therapeutic benefits, it may be nothing more than a drain on your finances – you aren’t experiencing any benefits nor drawbacks, yet you are paying for a substance that elicits no noticeable change in your physiology. In this case, it is relatively easy to stop taking inositol and save yourself the hassle of monthly or bi-monthly purchases.
Many inositol users report substantial therapeutic benefits without any noticeable or unwanted side effects. If you’re reaping the benefits of inositol without a single problematic side effect, continued supplementation is (likely) justified; you’re experiencing a net gain. Other users may have a bit more difficulty deciding whether to continue supplementation or discontinue altogether.
Someone who’s experiencing explosive diarrhea and painful stomach aches, yet experiences a strong antidepressant or anxiolytic effect – may feel as if they’re stuck in a catch-22. In this case, it is necessary to consider whether the benefit of the antidepressant and/or anxiolytic effect outweighs the diarrhea and painful stomach aches. For a person who was severely depressed with agoraphobia, the side effects may be a worthwhile tradeoff.
However, for a person who previously only had mild anxiety, the side effects may outweigh the benefit. For those that have experienced only side effects (e.g. dizziness, headache, etc.) after regular inositol usage, it’s likely worth discontinuing as a supplement. To weigh the pros and cons of inositol supplementation over time, I recommend keeping a daily journal to log your experiences.
Possible ways to reduce Inositol side effects
It would be nice if everyone could take inositol, feel amazing all the time, and experience no side effects. The problem is that some inositol users may struggle with tolerability issues. Fortunately, there are some strategies that may prove effective for mitigation of these side effects. Examples of such mitigation strategies include: taking the minimal effective dose, switching inositol subtype or brand, and/or avoiding other substances.
- Minimal effective dose: An effective strategy for reducing likelihood of inositol side effects is to stick with the minimal effective dose. Many people start supplementing with 3+ grams per day, and this may be too much for them to tolerate, especially without an introductory titration phase. Rather than starting supplementation with a high dose, consider starting low and gradually ramping up your dosage (each day) until you’ve reached the lowest effective dose for symptom management.
- Avoid other substances: Many individuals fail to consider that their inositol could be interacting with another drug and/or supplement that they’re taking. If you are able to take inositol as a standalone supplement for awhile, it may be worth doing so to determine how you tolerate inositol by itself. Sometimes people simply throw inositol in a haphazardly assembled supplement stack and an interaction and/or co-ingested agents may be culpable for side effects.
- Switch brands: Most reputable manufacturers sell quality inositol supplements. However, if you’re taking a particular brand and are experiencing side effects, you may want to switch to another brand and assess whether there’s any (subjective) improvement in side effects. Some individuals have switched brands and reported fewer side effects with one over the other. Formulation of inositol such as powder vs. tablets, additives, etc. – could impact side effects.
- Continue using: Another strategy to deal with inositol side effects is to simply continue using it. Although this strategy is relatively useless for long-term users, it may be helpful for short-term users simply to put up with side effects for a few days and/or weeks and continue using inositol. In some cases, an individual’s neurophysiology needs some extra time to adapt to elevated levels of inositol (from the supplementation). With continued usage, the body may adapt to the inositol and side effects may subside.
- Change inositol subtype: If you’re taking a specific type of inositol such as “D-chiro-inositol” you may want to consider switching to “myo-inositol” or vice versa. There’s no significant evidence to suggest that certain inositol isomers are associated with different side effects, but slight variations could be speculated. It may at least be worth testing another subtype of inositol to determine whether its side effect profile is favorable to another.
Have you experienced Inositol side effects?
If you’ve taken inositol, feel free to leave a comment mentioning whether you experienced any side effects. If you experienced side effects from inositol supplementation, note what they were as well as their severity (e.g. on a scale of 1 to 10). To help others get a better idea of your situation, share: your daily inositol dosage, the type of inositol (e.g. myo-inositol) and brand that you take, your total duration of usage, and whether you use other drugs or supplements along with your inositol.
Did you notice side effects from inositol immediately after you began supplementing? Or did they emerge after a longer term of usage? If you’ve experienced any side effects that were not mentioned above and/or know of any additional ways to decrease side effect severity, include them in your comment.
Understand that compared to most supplements and pharmaceutical drugs, side effects associated with inositol are generally negligible. However, no exogenous substance, especially when ingested at high doses, should be automatically considered devoid of side effects. When taking inositol, always listen to your body – if you don’t react well to it, there’s no need to continue taking it.
37 thoughts on “Inositol Side Effects & Adverse Reactions (List)”
I’ve started taking this for about 3 weeks now. I’m taking 2200mg/day spread out. For about 2 weeks now, I’ve been getting extremely bad chest/upper back pain. I almost thought I was having a heart attack!
I haven’t changed anything in my diet other than adding myo-inositol into it. Do you think this could be a possible side effect? I was going to stop taking it and see if the pains go away. It’s very unsettling.
Hi, I seem to do okay taking 500mg – 1000mg or less of Inositol. Seems to help with anxiety and mood. But, I recently bought powdered Inositol which has a scoop that when filled is 6g. They say you can take up to 12g so I thought I’d try the full 6g scoop for the last couple of days.
First day I think I had some mild headaches, felt a little off. Today, I felt worsening mood, more mild headaches, some worsening anxiety possibly, hard to tell. I just feel off. I’m assuming I’ve taken too much to start with.
My question is how long does it take for side effects to go away after stopping the product?
I have been taking myoinositol for 20 days now and here is my experience:
-I take 4 g a day to treat PCOS.
-I had celiac disease when I was a kid.
First week taking 4g of inositol (jarrow) in the morning with water was fine. I had some (one or 2 nightmares) but that was it. I did feel that my sleeping pattern changed a little, I was waking up more during the night. Second week I was feeling extremely tired. I needed more sleep, than my usual 8 hours.
I was waking up during the night or often and early morning hours I was basically in bed, but not really sleeping (5am-7am). 15th-20th day of taking inositol, one day I made the mistake to increase my dose from 4g to 8g. This day I went to yoga and I could not finish my class.
I felt lightheaded, badly, and even in the locker room I almost gained I was week and tied. This weekend I probably slept for 12-14 hours one single day total. I skipped one day to see, and I was feeling great again.
Now I learned my lesson. Start with slow doses and increase slowly. Our body needs time to adjust to it. Overall, the side effects for me were: brain fog, gas, stomach discomfort, weakness, sleepiness, and bad mood… really bad mood for a few days.
I love inositol. I take a big spoon every night and it helps me so much with my anxiety, OCD and insomnia. I’ve been talking it for about 4 months and I want to continue talking it. The only problem I have is that lately I’ve been feeling sleepy and tired during the day.
I tried Ovasitol, at the recommended dosage and became dizzy, nauseous throughout the day. By the end if the night it felt like food was just sitting in my stomach and I vomited all night. Next day I am still dizzy and unable to stand for very long.
I’ve been taking ovasitol for 3 months now to treat my PCOS while trying to conceive. Although I’ve had a lot of positive changes (first 28 day cycle ever, improved mood, less PMS), I’ve also had some negative ones. Most importantly I’ve noticed a significant decrease in libido and it has pretty much dried up my cervical mucous. This is very counterproductive when trying to conceive.
I’ve been taking My Inositol for about 2 weeks now. At first I had very bad mood swings. I’m usually very quiet and nice, I turned hateful and outspoken. I had a rash on my chest and itched all over. My skin is always warm but no fever. I continued the use and I feel calm and happy. The rash is going away…. But my skin is still warm! I have PCOS and I added DHEA to my daily routine. Glad i continued. I haven’t felt this pain free in my life. Even don’t feel like smoking or eating as much. The brand I take is called “Jazzee”, I hope this helps.
I started taking Ovasitol (2,000 mg of myo-inositol + 50 mg of D-chiro-inositol) twice daily a little over a week ago to treat my PCOS and *hopefully* improve my egg quality for my second round of IVF. So far I’ve noticed that I wake up every day with what feels like a hangover (headache), even though I have not been drinking at all during this time.
I’m incredibly, uncomfortably gassy, and my bowel movements have increased in frequency (although nothing like they were on Metformin!). The skin on my legs is also very itchy, almost like I have mosquito bites on them, although it’s clear nothing has bitten me, and I have no rash. I am slightly light-headed and “out to lunch”- I zone out for no reason, sometimes for quite a long time.
Although when I try, I can focus, and I do well, so I wouldn’t quite call it a brain fog. My sleep patterns have been affected, and I wake up frequently and for no reason. Another user reported taking this for trichotillomania, which I also have, and I noticed earlier today that I haven’t been pulling my hair like I usually do.
I also feel less depressed and have more energy than before I started taking it- although I had just had a miscarriage and came off taking high dosages of progesterone and estrogen to support the failed pregnancy, so I might just be feeling better by comparison. Ultimately I’m taking this to prep for an egg retrieval in June or July, so I can handle these symptoms until then if the result is favorable.
I start taking inositol a few days ago, low doses, in capsules. I did get some gas. The Dr. recommended I go up to 12 g per day, and cut back if I have gas problems. I then picked up powder at a specialty pharmacy and asked what could they recommend for gas.
The recommended some sort of chew-able probiotics – pricey, but it seems to prevent in me gas and diarrhea. I’m having the typical other problems, including some jitteriness, but hopefully that will dissipate in a week or so, as I adjust. I’m taking it for anxiety.
I commented a few months back about Inositol and low testosterone. I stopped taking Inositol, and 6 weeks later, my testosterone came back to normal levels. However, I was tested 6 weeks after this as a follow up (now having been off Inositol for 3 months) and my testosterone levels were lower than ever. So I am fairly confident the testosterone dip is NOT due to the Inositol. I will probably start taking it again as it does help with OCD.
I just took inositol (Myo) for the first time today and haven’t reacted well. It was powder and I would approximate my dose at around 500mg-700mg absolute maximum of 1g. (I took it from the edge of a teaspoon).
About 15 mins later I started to feel weird, my jaw felt tense and I started to feel very energetic but it was time to put my son down for a nap so I had to stay still and quiet which meant my mind was racing instead of my body. I got downstairs and had to do some exercise to try and calm myself down (I never exercise!).
I felt jittery and a little anxious, mental fatigue (for me my mind starts racing when I am very tired) so it’s like being tired and wired at the same time. I reacted a bit like how I do to caffeine and sugar as I have sugar issues. Just googled to see if it is the inositol as I also took taurine at the same time. I took some magnesium and zinc later in an attempt to calm myself down.
I know taurine can’t act as a stimulant when combined with other stimulants like caffeine but I have taken taurine before and not had anything like this, I take magnesium every day and zinc often. From what is read about inositol it was meant to help calm me and reduce anxiety and depressive feelings and instead it had me feeling a bit panicky and frankly like I’d taken a small dose of amphetamines (I have done so in the past).
I’m not sure if it perhaps down to the combination of inositol and taurine or just me reacting badly to the inositol. I’ve just read it is a sugar and I am very sensitive to sugar although usually would only react like this if I ate a tub of ice cream and nothing else type of scenario. It’s been nearly 3 hours since I took the inositol and I’ve been eating fats and proteins and drinking loads of water to try and flush it out and although I have calmed down a lot I am still not right.
In particular my eyes are stinging which is a reaction I have to sugar when I am tired. Maybe it is just down to it being a sugar I’ve reacted so badly. I’m not sure it’s worth me trying again, one thing is for sure it is powerful stuff and those who don’t suffer with anxiety etc but who need more energy may enjoy it but I’d start off very slow.
I can’t believe some of the doses I’ve seen recommended online, I think id be checking into a and e with palpitations at those doses. No wonder body builders use it though, I really felt like I needed to be busy and move my body and kept tensing my muscles while I was lying down with my baby. Pros and cons, but I’d be careful if you are sugar sensitive!
I’ve taken inositol on and off for years now – found it very helpful for anxiety, depression and OCD. These days don’t take it all the time but I will do during periods of high stress, or if I notice a return of any symptoms.
I usually take very high doses and sometimes on the first day or two have similar symptoms to these. I have gotten used to it now – as it always passes and the benefits start quickly for me… I take this as a sign it’s working and my body is adjusting.
My advice is start on smaller doses and work your way up slowly and also take with food, so before a meal.
I have been taking 4g of Myo-inositol for about a week now to treat severe symptoms of PCOS. I have seen a huge improvement in energy levels, my appetite levels have improved, I am not constantly hungry. I will say the first two days taking it I had vivid dreams, and the last two days I have had a headache that seems to only be improved by a cup of coffee.
It is that time of the month, so I cannot say for certain the headache is being caused by the Myo. Honestly so far I love the energy and stamina I feel with taking Myo. I have also incorporated Omega 3 and Vitamin D3 supplements.
I feel better than I have felt in over a year. I hope this helps women skeptical of trying Myo-inositol. I have nothing but good things to say about it!
Hi, I recently started taking relatively small doses of D-Chiro-Inoitol (Swanson 65 mg) and saw great results. I have fibromyalgia, and I saw an increase in stamina, clearer thinking and a more positive outlook. I read that Myo-inositol could be used in conjunction with the D-Chiro-Inositol for women with metabolic syndrome; so I added 1,000mg Myo-inositol to the D-Chiro-Inositol.
I took it for four days and immediately began experiencing bad nightmares and then fatigue and depression. Then, on the fourth day, I experienced a seriously painful fibromyalgia flare-up. I went back to taking only the D-Chiro-Inositol (65 mg) and I am feeling better already; as far as the depression and fatigue are concerned.
So far I have had a notable reduction in the fibromyalgia pain and have not seen a return of the nightmares. I guess time will tell. Thank you for your informative site.
Started inositol not quite a week ago at 500mg. I take it in the morning and have found that I get more done at work and I am somewhat less negative and paranoid. Downside: increased gas, evening nausea and stomach upset, occasional hot flashes, but also nightmares! I hope most of this resolves over time.
Ive been taking inositol for about 11 weeks. I’ve lost a full dress size. Just by changing how I eat and exercise. With PCOS I haven’t been able to lose the weight for 4 years! Ive cut out dairy and most carbs. I eat a lot of proteins, nuts, and drink a lot of water. I’ve only noticed crazy nightmares, restlessness, and sometimes extremely tired. I might need to cut back on the 4mg, but the weight loss is great! I forgot to mention I’m also taking vitamin D, calcium and folic acid, I’m taking citalopram for my moods and spironolactone for extra hair.
I have been taking high levels of Inositol for 4 years for OCD/Anxiety. It has helped somewhat, but I recently had my testosterone levels checked for another issue and they were extremely low for my age. Since Inositol has been shown to significantly decrease testosterone in women, it is entirely conceivable it could have the same effect in men. I stopped taking it and will retest in a couple of months.
It decreases testosterone in woman by making their ovaries to ovulate, then their ovaries produce less testosterone because after ovulation they produce progesterone instead. Why do guys think that it would work the same way in men if men have no ovaries?
Di… I was retested again after being off of Inositol for 3 months and my levels decreased again… so I am fairly confident that the low testosterone is NOT due to the Inositol. I actually started taking it again about 2 weeks ago as it does help with my OCD.
You’re right, there is no reason it should decrease testosterone in guys. I have been just trying to figure out why mine is so low… the doctors don’t really care, so I have been removing supplements/medications and retesting to see if there is any fluctuation. So far, I cannot find a cause… I may just have to face the fact that I’m getting old!
Hi, Sorry this is long but I wanted to try to give some feedback for some other women looking at inositol for PCOS issues unrelated to pregnancy. Here goes. First, I’m so sad to see so many negative comments about inositol. Although, I have not been on it long (3 weeks- Ovasitol), I have experienced a very positive change. I have PCOS, normal weight, eat very well for my condition and exercise.
I thought my condition was controlled until my spouse thought my constant absolutely freezing cold self was just not right. I did not realize it at the time but it was a combination too few calories and carbs. I bumped both of those up and kept everything whole foods and suddenly my body was less cold intolerant- by less, I mean a lot. Just to give you an idea… I was so cold all the time that I would start my car and warm it when the temperature outside was 17-19 degrees in the morning during the summer.
So increasing my calories and carbs solved my problem then. Oh so wrong! I gained almost 10 lbs in a month mainly on my belly. I felt hopeless. When I ate as a regular, healthy individual should within my correct caloric and carb “budget”, I felt better but could not stop gaining weight. When I ate less, I was freezing cold and constantly hungry… painful hungry, which I experienced regardless of the amount I ate but just to a more exaggerated extent.
I decided to research again and here I am 3 weeks on ovasitol and happy so far. My biggest issue has now become non existent – this being constant painful hunger. I do not crave and think about food ALL THE TIME, or drive myself crazy trying to talk myself out of eating the junk food which is suddenly in my presence at work, events etc, and I am satisfied with my meals now. Hallelujah!!! I did forget to mention that I was hungry all the time, painful hungry but could this be the answer I have been looking for all along?
I can eat the amount I need and feel satisfied and not gain weight? I am really hoping to take off the weight I gained with the help of ovasitol. I have noticed perhaps slightly less energy in the morning but nothing else. Please let this be the answer. It’s funny how you adapt to the way things are and realize how much more enjoyable life is when things are healthy and working right. Hopefully this helps someone else looking for their answer.
I just tried my very first dose of Inositol (In powder form by Jarrows), 600mg before my lunch and I started to get heart palpitations/major anxiety which is still the case even after eating a satisfying lunch (tuna w/avocado). I’m so glad that I didn’t try this at night time, I sure hope that it stops soon. I was hoping for it help me with my PCOS and anxiety but not sure if its going to work for me. :(
Any advice or recommendations on whether to take it after meals or before for effectiveness? Also, is it good to combine it with any other vitamins or minerals for better absorption? Granted, I just started an antibiotic to treat H. Pylori infection today which will continue for two months unfortunately… Please advice and or share your insight, thank you so much.
I have been taking inositol for about 2 years now. I am now just starting to have almost every one of the side effects listed on this site. I take a 500 mg capsule daily. This is for PCOS. I also take Synthroid. Does anyone know if there are lower doses of inositol than 500 mgs? I have yet to see one. Thanks, Steph
I took 1g of myo inositol for four days for PCOS but even after first dose I experienced acute restless leg syndrome (and arms) each night. It was just too ‘painful’ to continue. As soon as I stopped taking it the RLS stopped. I take 100mgs Sertraline per day which probably interacted badly.
I took the smallest dose of 1/2 tsp for 3-4 weeks, and it helped my agoraphobia tremendously! However, just after a month I realized I didn’t know where my pretty healthy sex drive disappeared to. I felt numb (sexually, not physically) but very happy everywhere else.
I decided to stop taking inositol. It has been about 3 weeks and it still hasn’t returned. Hoping it will eventually. If all returns as normal, I might try using it 2-3 days a year when we travel somewhere that increases my agoraphobia.
I have been taking 5g inositol +1200mg NAC daily for my trichitillomania. The effect on my behavior has been excellent – much less hair pulling, lower anxiety overall, better sleep, need less sleep, and doing less compulsive eating.
However, over time, I’m experiencing some odd side effects: skin sensitivity and eczema has been increasing dramatically, and in just the last couple of months, I have been noticing water retention in my ankles and feet. I moved in July, so I assumed it was because I was on my feet all day, but now, every once in a while, I notice my feet puffing up even when I haven’t been exerting myself.
I will try scaling back my dosage and see if this helps.
I’ve been taking inositol for 2 days now with very bad side effects. I took 1 gram the first day, and only a half gram the second. I got a very bad stomach ache, pelvic pain, gas, burping, nausea, vomiting, headache, insomnia, etc. It felt like food poisoning… And I felt slightly better after vomiting and getting it out of my system. After all that I’m not continuing. I was taking it for PCOS symptoms and anxiety.
Did the insomnia go away? I took inositol only twice and have severe sleep disturbances for several weeks now.
I have been taking Inositol for a month (PCOS) and the only change I noticed was a terrible acne outbreak… It was supposed to have the opposite effect, any ideas?
I had the exact same thing happen to me! I was taking 2 g per day and after about 2 weeks I broke out in terrible acne all over my upper body! Everything I have read says that it’s supposed to clear up acne. I’d love to know why that happened as well.
Same thing is happening to me! I’ve been taking Inositol for about 5 weeks and my skin is worse than before. Debating whether to give up or not?… Did you keep taking it or stop? I’m hoping things get worse before they get better?
Yes, I have been on it for about two months and acne is really bad. Thinking of cutting back or stopping.
I am taking a high dose of inositol for anxiety and have been experiencing stomach cramps, increased gastric inflammation, and vomiting. I have to cut back, although I feel that there have been great benefits too…
I started taking several grams a day for OCD and anxiety and it has made them both worse.
Hi! I’ve been taking inositol for a little and experience dizziness, headache, brain fog, major mood swings, and major insomnia, where I’ve never had trouble sleeping before. I am taking it to reduce my testosterone levels. Not liking the side effects.
I started taking Ovasitol (2,000 mg of myo-inositol + 50 mg of D-chiro-inositol) twice daily and I started experiencing heart palpitations and after that subsided, chest tightness and feeling shortness of breath. It’s as if it exacerbated my anxiety to an extreme point – at first I didn’t think it was the supplement, but after I discontinued using it my symptoms faded. I have no idea why it would do this – I’m considering trying a different brand/dose of inositol but right now I’m letting my body and mind relax after what felt like a month and a half of hell.
Hi! I have been use inositol four months 2g a day and last week I missed some pills and forgot to take it a few days. I had some very bad side effects like hot flashes, bad dreams, negative thoughts, anxiety, and I’m scared to continue taking it. I asked my doctor and she told me that I should continue taking it until I get pregnant and want to stop. Now it has been a few days taking 1 tablet a day or 1 g (1000 mg) and I’m trying to stop it, but need help.
hiba, it sounds like you have PCOS, right? Talk to your doctor again and ask about Metformin. But honestly, I have had BAD stomach cramps while on Inositol, but that’s nothing compared to all the symptoms I had while on Metformin. If I were you, I’d research Ovasitol, a blend of Myo-inositol and D-chiro-inositol. I’m planning to buy it after my bottles of Inositol run out.