Ginkgo Biloba is considered an extremely popular dietary supplement. In 2005, it was estimated that individuals living in the United States spent nearly $110 million on Ginkgo Biloba; a staggering amount of money. While there are some potential Ginkgo Biloba benefits such as cognitive enhancement, improvements in working memory, and increased blood flow to the brain – many of these benefits are overstated by supplement manufacturers and aren’t fully supported by science.
As a dietary supplement, Ginkgo is believed to have a complex mechanism of action. The phytochemicals within Ginkgo Biloba are thought to scavenge free radicals, thus yielding an antioxidant effect. In addition, Ginkgo has been thought to act as a platelet activating factor (PAF) antagonist, alter neurotransmission associated with Alpha-2 adrenergic receptors, and enhance the production of ATP.
While certain individuals may attain significant cognitive enhancement (i.e. a “nootropic” effect) from Ginkgo supplementation, it is always important to consider the associated side effects. Some side effects associated with Ginkgo Biloba may be dangerous (e.g. an allergic reaction) or may be difficult to put up with (e.g. dizziness). If you’re taking Ginkgo Biloba and/or are considering it, you should at least be cognizant of the side effects.
Factors that influence Ginkgo Biloba Side Effects
Prior to learning the potential side effects of Ginkgo Biloba, it is important to consider various factors that influence the occurrence of these side effects. Various factors that may contribute to the manifestation of side effects include: the specific type of Ginkgo Biloba taken, the format, the dosage, time span over which you’ve supplemented, interactions, and individual factors (e.g. genetics).
1. Type of Ginkgo Biloba
The type of Ginkgo Biloba supplement you take may influence the side effects that you experience. More specifically, factors such as: the manufacturer, format of administration, phytochemical contents, and specific extracts – can influence the side effects that you experience.
Manufacturing: Not all Ginkgo is grown, harvested, and manufactured with the same degree of quality control. Furthermore, the particular strain of Ginkgo you supplement may carry different side effects based on the country in which it was cultivated. If you want to minimize the likelihood of side effects, always purchase your supplements from a reputable brand.
Format: It is important to consider the fact that Ginkgo can be purchased in the formats of oral capsules, liquid gels, tea extract, and even in liquid extract. The format by which you consume Ginkgo Biloba may influence the number and severity of side effects that you experience, plus influence its absorption. For example, someone taking an oral capsule may experience different side effects than if they had tried the liquid extract form.
Phytochemical contents: It is also important to consider the phytochemical content of your specific Ginkgo Biloba. Different brands and formats of Ginkgo are likely associated with varying degrees of bioactive phytochemicals, which will influence the side effects that you experience. Examples of phytochemical extracts that may vary based on the brand include: flavonoids (myricetin and quercetin), and terpenoids (ginkgolides and bilobalides).
Many supplement company standards will not allow products to contain more than 3% stems and 2% of foreign matter; some manufacturers are more stringent than others. Specific active constituents within Ginkgo supplements include biflavones, polyprenols, proanthocyanidins, alkylphenols, and simple phenolic acids. It is also important to distinguish
Specific extract: A popular form of Ginkgo Biloba extract has been named “EGb 761.” This is a proprietary extract that may offer greater benefit when compared to standard Ginkgo Biloba supplements. If you are purchasing a specific type of Ginkgo, keep in mind that this may trigger certain side effects that you may not experience with another type.
2. Dosage (40 mg to 240 mg)
There are no definitive dosage guidelines associated with Ginkgo Biloba supplementation. Some people like taking a lower dose, while others may take a higher dose for greater perceived benefits. It is important to understand that when ingesting any substance, regardless of whether it’s a supplement or drug, side effects tend to increase in quantity and severity with the dosage.
Someone taking an extremely low dose of Ginkgo Biloba may not notice any side effects, whereas someone taking 120 mg three times per day (a total of 360 mg) may experience a throbbing headache and dizziness. To avoid severe side effects and adverse reactions, it is always recommended to take the “minimal effective dose.”
3. Time Span
The duration over which you’ve been taking Ginkgo can influence the side effects that you experience; time span of supplementation affects everyone differently. In some cases, a person may experience some short-term side effects, but may find that they dissipate after several weeks. In another case, a person may not notice any preliminary side effects, but may find that the side effects become unbearable after several months of supplementation.
- Short-term: Over the short-term, many people experience side effects as a result of physiological adjustment to the new stimulus (Ginkgo). The body may have more pronounced side effects immediately after supplementation due to the fact that an exogenous stimulus was introduced. For some people, side effects may be most pronounced over the short-term, but may fade after a couple weeks.
- Long-term: Other individuals may develop side effects after a longer term of supplementation. The long-term effects of Ginkgo supplementation aren’t well documented, and therefore it is unknown what sorts of complications may ensue. Some individuals may find that they build up a tolerance to Ginkgo, leading to them ingesting higher dosages over a long-term; this will cause more side effects. In addition, physiological changes may occur with daily supplementation over a long-term, resulting in the emergence of side effects.
While you may be quick to blame Ginkgo Biloba for the side effects that you experience, it is important to consider potential interaction effects. If you’re taking illicit drugs, drinking alcohol, ingesting pharmaceuticals (especially psychiatric drugs), or even taking other natural supplements – you are risking interaction effects. Should you suspect any potential contraindications, it is important to consult a medical professional as these could be dangerous.
The side effects you experience from Ginkgo may be intensified as a result of ingesting another exogenous substance. To get an accurate understanding of whether the Ginkgo it causing side effects – you may want to take it as a standalone treatment rather than as part of a “stack.” Those taking psychiatric drugs should be especially cautious of interactions.
5. Individual variation
Many side effects associated with Ginkgo Biloba supplementation can be chalked up to individual variation. Individual variation is why two people can take the same brand of Ginkgo at the same dose, yet one person experiences gastrointestinal pain and headaches, while the other experiences no noticeable side effects. Individual factors such as: arousal, neurochemistry, hormone levels, genetics, diet, sleep, etc. – may all influence side effects from Ginkgo Biloba.
For example, one person may be taking Ginkgo without food and experience an upset stomach, while another person may never get an upset stomach due to the fact that they take it with food. Besides taking it with or without food, it is important to consider the time of day that Ginkgo is taken. Although many side effects are likely associated with genetic differences, these are difficult to test – but may be possible in the future with companies like GeneSight.
Ginkgo Biloba Side Effects (List)
Below is a list of Ginkgo Biloba side effects. Understand that the number and severity of side effects you experience is largely a result of the aforementioned factors. It is also important to note that certain side effects such as: constipation, dizziness, headaches, and stomach aches – may be more common than others.
- Anxiety: Despite some evidence suggesting that Ginkgo could act as an anxiolytic, clearly this effect is not attained in everyone. Some people notice a significant increase in anxiety when they supplement Ginkgo. The herb can alter neurotransmission, blood flow, and possibly physiological arousal – all of which could contribute to increased anxiety.
- Appetite changes: There are few reports of appetite changes associated with Ginkgo supplementation. Nonetheless, most reports of appetite changes from Ginkgo supplementation were increases. It is unknown as to why the Ginkgo causes some people to feel hungrier than normal, but it is known to occur in select individuals.
- Blood pressure changes: There is some evidence to suggest that the supplement may alter blood pressure. Some people may find that it increases blood pressure, but more evidence suggests that it may decrease blood pressure – especially when used as a complementary therapy. It elicits an effect on Alpha-2 adrenergic receptors which could be the mechanism behind blood pressure alterations.
- Blood sugar changes: Some reports suggest that Ginkgo has potential to lower blood sugar levels. While the degree by which blood sugar is altered by Ginkgo supplementation is unknown, those diagnosed with diabetes or hypoglycemia should be cautious of this effect. In addition, professionals may advise against taking Ginkgo with medications that affect blood sugar.
- Constipation: Many individuals report experiencing constipation while taking Ginkgo. This may be due to the gastrointestinal effect elicited by the supplement. If you start supplementing with Ginkgo and find that your bowel movements slow, you may want to discontinue and/or lower the dosage to determine if a reduced amount could lessen this effect.
- Depression: There is small-scale preclinical evidence to suggest that Ginkgo supplementation may improve mood and/or quality of life. Despite these findings, some people notice that they become increasingly depressed when taking Ginkgo. The mechanisms responsible for increases in depression may be associated with physiological reactions, epigenetic reactions, and/or other neurotransmitter alterations from Ginkgo.
- Diarrhea: A subset of Ginkgo users may become constipated, while others may experience diarrhea. If you notice an increase in flatulence and that your ability to properly digest food has become impaired, it could be a result of the Ginkgo. While substances like Imodium may be helpful, experiencing diarrhea is a sign that your body isn’t tolerating the Ginkgo well.
- Dizziness: An extremely common side effect among Ginkgo users is that of dizziness. At lower doses the dizziness may be subtle, while at high doses, the dizziness may be pronounced. If you experience dizziness, you may want to scale back the dose to determine if a lower dose helps.
- Drowsiness: It is possible to notice an increase in drowsiness when taking Ginkgo. The drowsiness may be temporary and a sign that your body hasn’t fully adjusted to the effects of the Ginkgo supplement. Over time the drowsiness may subside, but if it doesn’t – Ginkgo may not be a good supplement for you.
- Dry mouth: If you notice that your mouth becomes dry and saliva production seems nonexistent – this could be from the Ginkgo Biloba. For certain people, dry mouth may be temporary and subside after a week or two of supplementation. For others the dry mouth will become so problematic that Ginkgo discontinuation is warranted.
- Gastrointestinal discomfort: Another known side effect of Ginkgo Biloba is gastrointestinal (GI) discomfort and/or pain. If you notice that your stomach hurts, your digestion feels altered, and/or a combination of both – it could be from the Ginkgo. Do not be surprised if your GI tract doesn’t like the Ginkgo. Also realize that certain formats of Ginkgo supplementation may be less likely to provoke GI discomfort than others.
- Headaches: Ginkgo Biloba can cause headaches of varying degrees of severity as a side effect. Some people may notice a slight headache, others may experience a significant headache, while another subset of users may experience a full-blown migraine. Most people will not experience migraines, but headaches are commonly reported among Ginkgo users.
- Heart palpitations: It is possible to experience changes in heart rate and/or experience fluttering sensations in your chest called “palpitations.” Some people may perceive these palpitations as their heart skipping a beat or beating too fast. If you start having heart palpitations immediately after supplementing Ginkgo, it’s probably no coincidence.
- Insomnia: Some individuals will find Ginkgo to produce an activating effect, mentally and/or physically. Increased neurophysiological activation can lead to insomnia or an inability to sleep. Should you experience insomnia, you may want to decrease the dosage of Ginkgo you’re taking and/or take it in the morning instead of the afternoon or night.
- Nausea: It is possible to become nauseous after you supplement with Ginkgo. This nausea may be related to an upset gastrointestinal tract (from the Ginkgo), but could also be a sign that you don’t tolerate this supplement and/or were taking too high of a dose. Those taking high doses may find that scaling down with the dose decreases insomnia.
- Nervousness: When taken in large doses, Ginkgo could cause increased nervousness. Should you experience an increase in feelings of nervousness, you may want to consider reducing your dosage. Nervousness may be a more common reaction among those with psychiatric conditions and/or anxiety disorders.
- Restlessness: Those that become increasingly stimulated as a result of Ginkgo may notice that they feel restless. If after taking Ginkgo you find yourself unable to sit still and are jittery, fidgety, and/or feel a need to move around – consider lowering the dosage or discontinuing.
- Sleepiness: Various users will find that Ginkgo Biloba improves their sleep quality and reduces insomnia. Others will find that supplementation makes them feel drowsy and sleepier than usual. For most people, sleepiness is not a common side effect. In many cases sleepiness subsides as a person adapts to the Ginkgo supplementation and/or alters their dose.
- Stomach aches: Many people report stomach aches when they take Ginkgo. These stomach aches are often a result of Ginkgo’s effect on the gastrointestinal tract. Should the Ginkgo alter the functioning of your gastrointestinal tract, you may experience stomach aches. To mitigate the stomach aches, you could try reducing the dosage and/or taking it with food (as opposed to on an empty stomach).
- Vomiting: Those who experience gastrointestinal distress and/or nausea may vomit as a result of Ginkgo Biloba. While vomiting is relatively uncommon, it may occur among those taking high doses and/or among individuals who are simultaneously ingesting other substances – leading to an interaction. Vomiting should be taken as a warning sign from your body that the Ginkgo isn’t well-tolerated.
Ginkgo Biloba Adverse Reactions
While certain side effects may be justified if the Ginkgo is providing therapeutic benefit, adverse reactions are never justified. Should you experience an adverse reaction, it is recommended to seek immediate medical attention. Adverse reactions are most likely to occur among individuals that have ingested other substances, are taking too high of a dose, and/or are allergic to Ginkgo Biloba.
- Allergic reaction: Individuals that are allergic to Ginkgo Biloba or other plants within the Ginkgoaceae family should not take this supplement. Those with an allergic reaction to Ginkgo Biloba may experience a variety of symptoms including: a skin rash, diarrhea, upset stomach, vomiting, swelling, muscle weakness, blistering, and itching.
- Anal sphincter spasms: An adverse reaction associated with Ginkgo Biloba is spasms of the anal sphincter. These spasms are characterized by rapid, uncontrollable expansion and contraction of the anal sphincter. Assuming you have no history of these prior to using Ginkgo, they are likely a sign that you don’t tolerate the supplement.
- Behavioral changes: Certain individuals may notice that their demeanor and behavior changes as a result of Ginkgo Biloba. Significant behavioral changes are not often reported with Ginkgo simply because it isn’t associated with major neurochemical alterations. Discontinuation is usually advised for those who begin to behave differently following Ginkgo administration.
- Bleeding risk: Another adverse reaction that some people experience is unexpected bleeding. Ginkgo is known to increase risk of bleeding, which could be due to its ability to increase blood flow to certain parts of the body. If you experience a bloody nose, bleeding within the mouth, anus, or vagina – it may be a sign of an adverse reaction.
- Blurred vision: Some studies suggest that Ginkgo may improve visual deficits, while others have found no such benefit. That said, not everyone experiences a visual improvement, some people may actually find that their vision becomes blurred after supplementation. These visual changes are unlikely to reflect actual changes to the eye, but are more likely to be associated with Ginkgo’s effect on the brain.
- Bruising: If you notice that you’re bruising easily after taking Ginkgo, this is a problem. An increase in bruising may be a sign that your body is unable to tolerate the supplement. Bruises could also be associated with Ginkgo-modulated blood flow changes and/or injury to the blood vessels.
- Faintness: In rare cases, some people may feel as if they’re about to faint or “pass out” as a result of using Ginkgo. Should you be overcome with faintness after supplementation, you may want to discontinue. Faintness could result from blood flow changes within the brain and/or could be associated with taking too high of a dose.
- Liver damage: Based on animal studies, there is evidence that Ginkgo could detrimentally affect liver functioning. In animal research, Ginkgo increased risk of liver cancer and damage. That said, the animal studies were conducted with extremely high doses of the Ginkgo. It is unclear as to whether this adverse reaction is likely to occur in humans.
- Pulse weakens: It is possible to experience a weakened pulse when taking Ginkgo. Weakening of the pulse is usually associated with clotting. Ginkgo is known to alter the functioning of blood vessels and blood flow, which could trigger the adverse reaction of a weakened pulse.
- Seizures: In rare cases, certain individuals may experience seizures and/or convulsions. Seizures are most likely to be triggered in people with a history of seizures, as well as among those taking high doses of Ginkgo. In addition, seizures could also stem from an interaction effect between Ginkgo and another substance.
- Shallow breathing: While rare, some people may notice that their breathing changes and their breaths become shallower. Should you notice any respiratory effect from Ginkgo, seek immediate medical attention. Shallow breathing could be due to a variety of neurophysiological reactions to the Ginkgo.
- Skin rash: Those that develop a skin rash from Ginkgo are experiencing an allergic reaction. While a skin rash isn’t a common reaction, it’s a sign that you’re unable to tolerate Ginkgo. For some people, all it takes is the touching or handling of Ginkgo to cause blisters, itchiness, swelling, and possible pain. Some sources estimate that the itching can persist for up to 2 weeks.
Ginkgo Biloba: Weighing the Therapeutic Benefits (Pros) and Side Effects (Cons)
If you’re supplementing with Ginkgo Biloba, it is important to compare the therapeutic efficacy with the prevalence of side effects. Some people won’t derive any significant therapeutic benefit from Ginkgo Biloba, and therefore it should be relatively easy to justify discontinuation. Nobody should be wasting money on a supplement that isn’t providing them with some sort of measurable health benefit.
Individuals that are able to derive significant benefit from Ginkgo Biloba (e.g. memory enhancement) may experience side effects that make them think twice about supplementation. It is up to you to determine whether the health benefits associated with Ginkgo Biloba are substantial enough to put up with any side effects. For example, if your memory improves significantly, but you also become constipated, experience migraines, and develop a skin rash – discontinuation is the better bet.
Most people will be able to clearly tell whether the benefits they derive from Ginkgo outweigh any costs (i.e. side effects). Some people may experience nothing but benefit and no substantial side effects; this is the ideal outcome.
Have you experienced side effects from Ginkgo Biloba supplementation?
If you’ve taken Ginkgo Biloba (or still do), feel free to leave a comment discussing whether you experienced any side effects. If you experienced side effects from Ginkgo Biloba, provide more details such as: the brand you’ve been taking, your daily dosage, time of day you take it, whether you take it with food, and the duration over which you’ve supplemented. Keep in mind that while certain side effects are subject to individual variation, some are clearly more common than others.