≡ Menu

Low Serotonin Levels (Symptoms)

Everyone’s heard that low serotonin levels are associated with depression. While the serotonin theory of depression may be valid for some people, clearly not everyone with depression has low serotonin. However, we do know that for the majority of people, SSRIs (selective-serotonin reuptake inhibitors) help treat depression.

This has lead many people to wrongfully conclude that since a drug that elevates serotonin helps depression, the original problem must’ve been low serotonin. This is a problematic way of thinking about depression and one that I preach against. Tweaking other neurotransmitters is also capable of causing depression. My theory is that the biochemical signature of depression is subject to individual variation.

That said, it is clear that low serotonin can cause problems in psychological functioning. For you or someone else, the problem may be directly related to serotonin levels. If you have low serotonin, you may feel highly stressed, have sleeping issues, struggle with anxiety and/or panic attacks, and be more susceptible to depression.

Low Serotonin Levels (Symptoms)

Normal serotonin levels help regulate sleep, reduce pain, make us feel calm, and improve our mood. Abnormally high serotonin such as that observed in the cases of “serotonin syndrome” can detrimentally affect coordination, make us feel sick, and even cause death. Below is a list of symptoms that you may experience if you have suboptimal levels of serotonin.

  • Anxiety: Those with high levels of anxiety generally tend to have low levels of serotonin. While serotonin usually isn’t the only neurotransmitter to blame for a person’s anxiety, increasing levels of serotonin are known to be an effective way to reduce anxiety. This is why those diagnosed with anxiety disorders or chronic anxiety tend to benefit from serotonergic medications.
  • Carbohydrate cravings: If you have low serotonin, you may find yourself craving carbohydrates and/or other sweets. Carbohydrates are known to have an indirect effect on serotonin levels. This is because when your body ingests carbohydrates, allow tryptophan to become more available, which gets converted into serotonin. Craving carbohydrates is common even among those without low serotonin due to the fact that many carbs contain gluten, which is also addictive.
  • Cognitive impairment: Serotonin may not be as important as dopamine for cognitive function, but it still helps. Serotonin has been found to enhance cognitive function and in some cases correct various aspects of cognitive dysfunction. Perhaps the biggest drawback associated with low levels of serotonin is that of poor memory consolidation.
  • Depression: There is clear evidence that for many people, serotonin increases help to ward off depressive symptoms. This does not mean that everyone’s depression is only caused by low serotonin, but it does mean that low serotonin could be contributing to the problem. Many people find that when their serotonin levels are increased naturally or artificially, their depression subsides.
  • Digestive problems: Studies have shown that serotonin signaling in gut plays a key role in the development of irritable bowel syndrome. Increasing levels of serotonin often help correct this condition and improve digestion. Those with many other symptoms on this list and digestive problems may find that low serotonin is partially to blame. Normal levels of serotonin tend to help promote healthy digestive function.
  • Emotional sensitivity: Those with low levels of serotonin may also be more emotionally sensitive than those who aren’t. Some people with low serotonin may take subtle comments or jokes as personal attacks due to the fact that everything seems serious. Their low mood may result in them becoming increasingly emotionally sensitive.
  • Fatigue: In some cases low serotonin can cause a significant degree of fatigue. If you feel consistently lethargic or tired, it could be a result of deficient serotonin levels. This fatigue is a common occurrence upon discontinuation from a serotonergic drug and often persists until serotonin levels are replenished.
  • Headaches: There is a link between serotonin levels and headaches. The lower your level of serotonin, the more susceptible you will be to developing headaches. Severe headaches or migraines often improve when a person increases their serotonin level.
  • Insomnia: Low serotonin is also associated with insomnia due to the fact that serotonin levels help with melatonin production. If a person has an abnormally low level of serotonin, their arousal may not decrease at the proper time of night in accordance to their circadian rhythm. This is likely a result of inadequate melatonin, stemming from low serotonin.
  • Irritability: Another sign that your serotonin levels may be low is irritability. Minor annoyances may trigger full-fledged anger and you may find yourself snapping at others. Intense anger is often improved when serotonin levels are increased within a normal range.
  • Libido changes: Most often people notice an increase in their libido (sex drive) when serotonin levels drop. Low levels of serotonin are associated with an increased desire to have sex and horniness, whereas higher levels of serotonin are associated with a decreased sex drive, but increased emotional connectedness or bonding.
  • Light sensitivity: If it feels as if bright light hurts your eyes or you’ve become extremely sensitive to light, it could be a result of low serotonin. Since serotonin helps us stay calm and improves our mood, little things like bright sunshine may make a person with low serotonin levels feel uncomfortable.
  • Low self-esteem: Another sign of low serotonin is that of low self-esteem or low confidence. If you have poor social confidence or can’t seem to stay calm in seemingly normal situations, low serotonin could be a contributing factor. This is why when some people take serotonergic antidepressants, they become more confident and social.
  • Mood swings: It is common for people to experience mood swings when their serotonin is low. Acting aggressively or more emotionally sensitive in social situations are a couple of signs that serotonin may be a contributing factor to mood swings. If you find yourself angry, aggressive, depressive, and anxious – serotonin levels could be a factor.
  • Obsessive thoughts: Those who have obsessive thoughts often feel trapped by their own uncontrollable thinking. These obsessive thoughts may become so severe, that a person feels as if they must act out compulsions (as seen in patients with OCD). Low serotonin can cause obsessive thoughts even among those without OCD. When the serotonin levels are increased, the obsessions may diminish.
  • Overeating: As we know, there is a link between serotonin production and carbohydrate cravings. We also know that a person may feel depressed and/or anxious with low serotonin. Therefore as a means to escape these uncomfortable emotions and satisfy the “cravings” it may be more common for those with low serotonin to overeat.
  • Pain sensitivity: There is an association between pain tolerance and serotonin levels. Those with higher levels of serotonin tend to have a greater ability to handle pain. Those with low levels of serotonin become increasingly sensitive to even minor pain. Handling pain can be difficult for someone with insufficient serotonin.
  • Restlessness: Many people with low levels of serotonin end up feeling very restless or experiencing restless leg syndrome (RLS). Discontinuing a selective-serotonin reuptake inhibitor (SSRI) is known to make restless leg symptoms worse. Low levels of serotonin are known to make restlessness and increase the severity of RLS.
  • Sleep problems: It’s difficult to sleep properly without adequate levels of serotonin. Low levels may cause anxiety and are associated with the stress response. This may mean that you aren’t getting proper restorative, deep sleep throughout the night. If your brain is in overdrive and you’re unable to relax, it’s probably going to make for a miserable night’s sleep. Plus melatonin is manufactured from serotonin. Without adequate serotonin to facilitate melatonin production, you may not feel sleepy when you should.
  • Social withdrawal: Certain individuals may resort to isolating themselves from others and withdraw from social events as a result of low serotonin. Moderate levels of serotonin help promote calmness and agreeableness in social situations. If a person isn’t getting proper levels of this neurotransmitter, they may see no purpose in even trying to push through the social discomfort they experience.
  • Sound sensitivity: Some people may become extremely sensitive to moderate or loud sounds in the environment. Modest or even low decibels may seem to bother those with lower than average levels of serotonin. Hearing these sounds may make an individual with low serotonin feel uncomfortable due to an increased stress response.
  • Suicidal thoughts: Some people with low serotonin may experience suicidal thoughts as a result. Anyone that’s ever taken an antidepressant and gone through withdrawal may have experienced an increase in suicidal ideation as a result of low serotonin. Taking a serotonergic medication often helps decrease these thoughts.
  • Weight gain: Due to the fact that low serotonin makes people crave carbohydrates, increases likelihood of overeating, saps a person’s energy, and makes them depressed – weight gain is an inevitable byproduct. Certainly not everyone with low serotonin is going to gain weight, but it may increase the probability.

How to Increase Serotonin Levels

Fortunately if you feel as if low serotonin is impairing your mental performance and ability to function in social situations, you can take some steps to boost it. Realize that when elevating serotonin levels, levels of other neurotransmitters may be indirectly affected. Also keep in mind that certain methods produce quicker results than others.

  • Dietary changes: Making some simple dietary changes can elevate your serotonin levels. Consider planning to consume more foods that are rich in tryptophan (an amino acid that your body converts to serotonin). Carbohydrates will help make tryptophan more available, and thus can be an effective short-term strategy for raising serotonin. However, carbohydrates may be a problematic strategy in the long-run due to other effects (e.g. on glucose).
  • Exercise: There is some evidence that consistent exercise may be effective at elevating levels of serotonin and improving its synthesis. It is believed to do this by increasing the availability to tryptophan as a result of fatigue. While the links between consistent exercise and serotonin are somewhat vague, researchers hypothesize a connection.
  • Medications: The easiest way to increase serotonin levels is by taking a pharmaceutical grade serotonergic medication. Most commonly prescribed drugs that target the serotonin system are SSRIs (selective-serotonin reuptake inhibitors). These are effective for increasing the levels of extracellular serotonin in a short period of time. Other options include: SNRIs, atypical antidepressants, and tricyclic antidepressants.
  • Sunlight: You may also want to consider increasing the amount of sunlight exposure you get during the day. Low levels of Vitamin D are associated with slower production of serotonin in the brain. If you want to increase the speed by which serotonin is produced, get yourself outside and under the sun. Supplementing Vitamin D is unlikely to yield the same effect as natural exposure.
  • Supplements: There are several supplements that you could take if you suspect that your serotonin levels are lower than average. Assuming you’ve already made dietary changes, supplementing with either L-Tryptophan or 5-HTP could be beneficial. L-Tryptophan is likely safer than 5-HTP, but neither should be consumed over the long-term because the effects may be dangerous.

Conditions associated with Low Serotonin Levels

There are a variety of conditions that may be influenced by low serotonin levels. Keep in mind that not everyone with these conditions necessarily has “low serotonin.” However, many of these conditions are improved by increasing serotonin levels.

  • Autism: It is thought that various cases of autism may be partially caused by dysfunctions in the serotonin system. Researchers believe that those with autism may have low levels of serotonin and mutations in the process of its transportation throughout the brain. Treatment for autism sometimes involves an SSRI medication to help increase serotonin.
  • Anxiety disorders: Another condition associated with underproduction of serotonin is that of anxiety. Those who are frequently anxious are thought to lack serotonin to help promote calmness and relaxation when necessary. The low serotonin makes the person feel as if they are in constant “fight-or-flight” mode, and unable to reduce psychological or physical arousal.
  • Eating disorders: Those with eating disorders often suffer low self-esteem, poor confidence, anxiety, and depression. There is a speculative link between low serotonin and dysfunction of its neurotransmission and eating disorders like anorexia, bulimia, etc. Many people with eating disorders find that taking an antidepressant to boost serotonin levels tends to help.
  • Fibromyalgia: This is a condition characterized by body aches, muscle pain, and tenderness. Individuals diagnosed with this condition tend to be highly sensitive to pain and have a low threshold for pressure. It is thought that dysregulation of serotonin metabolism may be a contributor to this condition. Some people experience relief from certain symptoms by elevating their levels of serotonin.
  • IBS: Serotonin plays a key role in the process of digestion and gut functions. Those with IBS or irritable bowel syndrome tend to not have enough serotonin for proper digestion. This leads to a person experiencing excessive diarrhea, abdominal pain, or flatulence. It is a very common condition affecting millions of people. Many people find relief from increasing their serotonin levels with an antidepressant medication.
  • Major depression: Those diagnosed with major depressive disorder are thought to have serotonin deficiency. Although not everyone who is clinically depressed has a problem with serotonin, elevating low serotonin in an individual who is deficient tends to improve mood and eliminate depressive symptoms. SSRIs are considered a first-line treatment option for those with depression.
  • Migraines: Studies suggest that those with migraine headaches tend to have lower than average levels of serotonin in the brain. Various antidepressants tend to increase levels of serotonin signaling, which reduces the likelihood that migraines will occur. Melatonin, a hormone that is strongly linked with serotonin levels is also related to migraines. For many people, boosting serotonin reduces headaches as well as the severity of the pain that they inflict.
  • OCD: Obsessive compulsive disorder has been associated with lower than average levels of serotonin. Administration of an SSRI tends to be an effective treatment for reducing obsessive, intrusive thoughts as well as compulsions. While low serotonin may not be the only cause of this disorder, it has been thought to play an essential role.
  • Sleep disorders: Some people with sleep disorders and wakefulness disorders have problems with serotonin levels. Pharmacological administration of serotonergic agents tend to improve sleep quality in those with sleep disorders. Low serotonin can manifest a variety of sleep issues including: insomnia, hypersomnia (excessive sleepiness), and poorer sleep quality.
  • Undermethylation: Those with undermethylation have mutations in the MTHFR gene which leads to low levels of SAM-e, which helps donate methyl. It is estimated that between 15 and 20% of individuals who are undermethylators end up depressed, partially as a result of low serotonin levels. Fixing the methylation problem with dietary interventions and a supplement regimen can lead to normalized serotonin levels.

Have you ever had low serotonin levels?

If you’ve experienced low levels of serotonin, feel free to share some of the symptoms you’ve endured in the comments section below. While many people believe that they have low serotonin, believing is often different than the reality. Having neurotransmitter blood tests conducted can offer some insight as to whether you truly have low levels of this neurotransmitter, but even blood tests are thought to be a “crap shoot” in terms of accuracy.

Those that have taken serotonergic drugs such as antidepressants for awhile and stop cold turkey likely experience low serotonin during withdrawal. Most people that withdraw from an SSRI after consistent, prolonged administration have experienced some effects first hand of low serotonin. It takes time to replenish depleted levels, but with consistent effort, serotonin levels can be increased to a healthy range.

I believe that I dealt with low serotonin after playing “antidepressant roulette” (or serotonin roulette) for a couple years and then discontinuing treatment. This likely left me to face an antidepressant-induced chemical imbalance due to the fact that my brain had become used to receiving the extra serotonin, it developed tolerance to the drug, and then supply got cut off. There’s no way to know for sure whether it was low serotonin, but it would make logical sense that serotonin had something to do with it.

Related Posts:

{ 15 comments… add one }
  • ewa kukla April 17, 2015, 1:12 am

    I have my son suffering from all symptoms mentioned above. He is 18 years old. I am afraid to give any medication, people say it is very unsafe. I don’t know what to do, where to get help, it is really bad, he destroyed many things. I have had enough. Otherwise he is very smart, there is no mental retardation.

    • Marcus February 26, 2016, 5:09 am

      Hi Ewa, he is so young and the male brain does not fully develop until 25 years old. I have had anxiety and really bad panic attacks for 4 years, it has been unbearable at times to say the least. I have tried and SSRI Lexapro and was on it for 16 months, I came off it and it was hell everything got so much worse. SSRI’s leave your brain with low serotonin even lower than before.

      Anxiety and depression can be caused by a lot of different things e.g. thyroid, hormones, low serotonin, adrenal fatigue. You need to find out why he is experiencing the issues he is facing, “to cure it” SSRI’s only mask the issue, short term may make it better but long term it definitely doesn’t and you cannot stay on them forever.

      For me it has been a battle, I had seen at least 6 doctors about this and they have all thrown different medication at me, I knew it was not good for my health and never filled the scripts except for the very first time. I am glad I didn’t, it has been 5 months since I got off lexapro and I have not fully recovered from it yet.

      I have found myself a specialist doctor who deals with all this stuff, hormones etc. We are positive we have found the issue and will know exactly what it had been in a few weeks. I started taking some natural stuff like 5HTP and cysteine with a testosterone booster. It has been two days and honestly I’m feeling like I’m getting back to my old self.

      Lucky for me I have a very supportive mother and I am strong willed and knew there was nothing wrong with my head! He is your son, please take care of him as much as you can. Don’t take no for an answer, don’t fill any scripts the doctor gives him until you find out what the actual issue is. And it could be the simplest thing.

      Take care, he will get through this; the natural way is the best way. Be persistent.

  • Stevie July 14, 2015, 3:42 am

    Yes, for my autism spectrum disorder my doctor gave me the lowest dose of Lovan in a low allergenic version. Various symptoms of my health immediately got worse, I swelled up and was in a stupor started falling over (my legs normally give out temporarily and recover but I would just go down with this). I can’t remember most of the other symptoms (after 5 or so days I read the information that came with it and found I had had just about every negative reaction listed), but I kept halving the Lovan till I could tolerate it (1/6th the lowest dose) the doctor wanted me to keep going on it.

    By the end of 4 or 6 weeks I was getting uncontrolled movements in my arms, some face issues and my feet would slap on the floor when I walked, as I could no longer rotate angle my foot, and started walking in a spastic way, so I stopped it. Later I tried tryptophan from a local store, in very small doses, but then read about the therapeutic dosage which was many many times the pinch I was having. I instantly got a bulging head and hissing noise, agitation etc. Every time I would even use much lower amounts I got these symptoms.

    It turns out it also raises adrenal function, which I get low symptoms of including low sodium, and pain to bright light and loud noise. I then read about a serotonin receptor hypothesis, that the reason for depression was an overabundance of receptor expression due to low serotonin levels. That the reasons SSRIs took so long to work rather than instantly, was there slow down regulation of these receptors over the weeks.

    So I started building up lower doses of tryptophan to reduce receptor expression, and that eliminated the reaction. It was my hypothesis that my problem might have been partly low dopamine leading to lower serotonin up regulating receptor function too high. That serotonin syndrome in some people might work on this mechanism. Life is complicated.

  • Shelley October 26, 2015, 7:20 pm

    I have just had my blood tested for serotonin and it is low, it should be 80-450 but mine was only 10, I have been diagnosed with fibromyalgia and had an eating disorder when I was a teenager. Interestingly my family has had drug and alcohol related problems, I believe due to low serotonin levels!

  • Chrissy February 14, 2016, 11:25 am

    I am suffering from most of the symptoms above and had my levels tested. Level was low. My family history is a father and a grandmother with OCD so that could be where the low levels stem from.

  • Aiman February 24, 2016, 8:08 am

    I suffered from depression and anxiety 12 years ago. SSRIs helped reduce the effects of depression, but I was never the same person I know I am. I tried many things until recently I started spending as much time outside as I can. Sunlight is the solution to improve serotonin levels. You don’t have to be directly under the sun, but your eyes need to be exposed to the brightness for as long time as you can. After 10 days I started to notice significant improvements. Trust me, try to avoid SSRIs and any other medications (I tried more than 6 types). Fix your lifestyle, mainly the sun.

  • Sarah March 25, 2016, 1:32 am

    I had terrible anxiety, high sex drive, raging appetite, forgetfulness, low self esteem, brain fog, fatigue, social withdrawal, abnormal wake pattern between 4 – 5am and digestive issues. Doctors were clueless. I had many, many tests done and the only abnormal result was my serotonin level was really low at 20. I started 5-HTP and noticed improvements within a few days of taking the supplement. Switched to Paxil and am amazed at how different I feel. I was very hesitant to take an antidepressant but now I wish I started years ago.

    • Damien April 21, 2016, 4:12 pm

      Hi. What dose are you on for the paxil and for how long? I too found low-dose citalopram helped with my digestive issues for a year or so then pooped out and I didn’t want to up the dose. Low dose St. John’s Wort seems to help me too, which I have recently started.

  • Roni April 30, 2016, 6:26 pm

    I have had depression since I was a small child, including severe anxiety with panic attacks, low self esteem, social anxiety, insomnia, severe PMS, night terrors, and the list goes on and on and on… I tried anxiety and depression medications in my early twenties (which only worked temporarily so I stopped using them) and just winged it through life over the next twenty eight years as best as I could.

    A few months ago I discovered 5htp and began taking it. To make a long story short, all of my symptoms (described above) have disappeared as well as car/motion sickness, many allergy symptoms, that feeling of being “off balance” in my equilibrium, lack of motivation, and rational thinking has replaced what would often seem like paranoia. My list of symptoms was too extensive to list.

    I do not take any other medications and won’t. I use approximately 600mg of 5htp throughout the day (approx every 5-8 hours for approx 4 months now) and feel wonderful! I am more social as well as have better self esteem and make better decisions. I don’t know how it can be bad for a person over the long term, but I plan to take it continuously until I don’t feel like I need it anymore.

    I may stop for 24-48 hours on occasion, but I haven’t yet. I feel like this was my original problem (serotonin deficiency) and that I now have a cure (like taking vitamins!).

    • Michele Rafferty June 27, 2016, 3:56 pm

      This is wonderful. Are you doing anything else to help? Diet, exercise?

  • brian longhurst June 12, 2016, 10:18 pm

    Now taking probiotics along with sertraline has had a great improvement in my depression, which suggests my gut has been very poor for many years with associated other problems like IBS, twisted bowel, restless leg syndrome and others.

  • dee mccreanor June 19, 2016, 4:45 pm

    What type of physician is best at understanding all the symptoms that lack of serotonin causes and can prescribe sufficient medications??

  • BJ August 7, 2016, 2:26 am

    There is also convincing evidence that too much serotonin can cause the exact same symptoms as not enough. Anxiety, losing balance, insomnia, depression, low self-esteem. I wish the symptoms of too high and too low were different instead of exactly the same. To experiment even with milder natural substances that raise serotonin just to test personal results is scary, as I don’t know if I can tolerate being worse than I am now.

    But to do nothing, or even experiment with lowering serotonin is also scary in case that would also make me worse. My doctor doesn’t believe serum serotonin blood tests really show what’s going on in the brain itself and doesn’t support them. Though I could switch doctors, I agree with him. As you said, they’re a crap shoot, anyway.

    I just wish there was more discrepancy between too much and too little instead of the symptoms being exactly the same. Do you have any thoughts on too much serotonin? I don’t mean outright overdoses of drugs that cause serotonin syndrome, but rather, someone like me who isn’t taking drugs, just wants to take foods with some tryptophan, chamomile tea, holy basil tea and passion flower tea without making myself worse in case I already have too much.

  • Anonymous August 10, 2016, 9:11 am

    Ugh, sorry to go anonymous for this, kind of a touchy subject I’m about to bring up… I’ve got a ton of these symptoms and am starting to believe low serotonin is the cause. Just wanted to check two more “conditions” and possible relationship with low serotonin with readers/commenters:
    -Is anyone here suffering from low serotonin also diagnosed with AD(H)D?
    -Are there any guys with low serotonin that also struggle with premature ejaculation?

  • Brooke August 18, 2016, 3:53 pm

    I believe I have been suffering from low levels of serotonin all my life. I started a low dose of Zoloft (25mg daily) as a way to treat my IBS, which has effectively disappeared after years of conjecturing what food allergies/sensitivities I was living with (in the end I had none, just anxiety). From a young age, I have dealt with hyper-sensitivity, hyper-vigilance, anger, mood swings, PMDD, fatigue, brain fog, cyclical depression, high levels of anxiety, major irritability, and joint pain.

    Since I have been on this low dose of Zoloft I feel like a completely different person. I am more patient, and feel less irritated by everyday annoyances. I still have complex feelings, but feel like there is a cap on my reactions to my feelings, which is wonderful. For a long time I felt like I was an emotionally weak person for at times not being able to control my mood swings and outbursts.

    Now I realize I just needed help getting my serotonin levels up to a normally functioning level. I am so relieved that I found some answers to so many mysteries that have been plaguing me since childhood!

Leave a Comment