L-Tryptophan for ADHD: Amino Acids Reduce Symptoms

Attention Deficit Hyperactivity Disorder (ADHD) is considered a neurodevelopmental disorder. Currently, the treatment for this disorder is primarily with various forms of the central nervous system stimulants methylphenidate and amphetamine. There is very little research on the long term effects of these drugs, and what we know from the research that does exist is not encouraging.

For instance, we know that long-term use of stimulants, even as prescribed by a physician, can lead to tolerance and the need for higher and more frequent doses to get the desired effect (National Institute on Drug Abuse, 2018).

There are some nonstimulants that were approved for use with children who do not respond well to stimulants (FDA, 2017). The nonstimulants include Strattera (atomoxetine), Intuniv (guanfacine), and Kapvay (clonidine).  These were approved for this use quite recently, so the effects of long term use has yet to be determined (FDA, 2017). Atomoxetine was approved in 2003; Guanfacine was approved in 2009; and Clonidine was approved only in 2010.

Unfortunately, people are needing to choose between the ADHD symptoms and the often equally cumbersome side effects of nonstimulants. The use of nonstimulants is not nearly as common as the use of stimulants, so this post is going to be focusing on stimulant use. The amino acid we will be focusing on here is L-Tryptophan. L-tryptophan is a precursor to serotonin, which means it is nutritionally essential for the production of serotonin.

There are various studies underway which are trying to determine the “cause” of ADHD. I personally don’t believe there is one specific cause for all who are diagnosed with ADHD, and it is also widely accepted that regardless of the diagnosis, there are many factors that may exacerbate ADHD symptoms (diet, environmental exposures, etc). The very fact that stimulants work for many children but not ALL of them is at least one good indicator that the root cause of ADHD may not always be exactly the same from one child to the next. We are all unique individuals, after all.

Okay so you may be asking, “How does a stimulant work to help calm down and focussomeone? A stimulant should stimulate right?.” Well, yes and no.

It should be noted that the mode of action of stimulants in ADHD is not well understood. Just as there are various theories for the cause of ADHD, there are also various theories on how drugs work to affect ADHD. This means that stimulants are given to ADHD patients, and they work, but we don’t exactly know how they work. One theory is that they prevent the reuptake of dopamine and norepinephrine, which increases the activity of those neurotransmitters in a part of the brain called the prefrontal cortex. The prefrontal cortex is responsible for impulse control, decision making, moderating the way we behave in social situations, and complex planning. Another theory that I find interesting is the hypothesis that rather than an issue with the quantity of available dopamine and norepinephrine, there is some kind of disturbance in the blood brain barrier that does not allow enough of the amino acid tryptophan to be transported across it (Ahlin et al., 2011).  Tryptophan deficiency within the brain would not necessarily appear in typical blood work.  To clarify, a person may have plenty of tryptophan circulating in their blood, but if the blood brain barrier won’t let enough of it in, there is a brain deficiency (and there is not really a safe way to study brain deficiencies). And if there is a brain deficiency of tryptophan it can be assumed that there is also a serotonin deficiency since the brain utilizes tryptophan to create serotonin.

Wait, weren’t we talking about dopamine? Yes, indeed we were. Hang with me here. Serotonin and dopamine essentially work together–in a way, they are constantly balancing each other out.

The serotonergic system directly influences the dopamine system, and a chronic deficiency of serotonin at the point where brain neurotransmitters allow communication between two neurons (called a synapse) is known to trigger symptoms of ADHD (Banerjee & Nandagopal, 2015).

So a serotonin deficiency could negatively impact dopamine levels and activity in the brain. This may be why L-tryptophan supplementation significantly alleviates ADHD symptoms (Banerjee & Nandagopal, 2015). To me, it makes sense that increasing the available circulating tryptophan via supplementation or diet would help more of it move across the blood brain barrier.

This is further supported by the prevalence of ADHD among alcoholics, as the consumption of alcohol increases brain concentrations of serotonin (WebMD, 2018).

Perhaps ADHD patients are more prone to alcoholism partly because they are deficient in serotonin.  There is a lot of literature (in books, journals, and online medical resources) that suggests supplementation with tryptophan helps to alleviate the symptoms of ADHD.  I have also read many anecdotal stories from adults diagnosed with ADHD and from parents with children who have ADHD who found that tryptophan or 5HTP supplementation helped tremendously. 5HTP is known to increase serotonin levels and is commonly used in combination with other amino acids for various health issues.

Finally, L-tryptophan may not work for everyone with ADHD.  Remember, each individual in unique.  There are many other alternative approaches, and I encourage you to do your research before any final decisions are made.

If you do decide to give your child a tryptophan supplement (which is found in animal and plant proteins that we eat every day), or if you decide to take it yourself, it should be under the care and supervision of your physician.

There is a brand called Lidtke that makes a chewable tryptophan tablet. I have tasted it, and can tell you that it smells like pancakes and tastes like maple syrup.  In general, it is best to take a pure form of L-tryptophan such as this powder version from NutraBio. Pure L-tryptophan doesn’t taste wonderful, but its not terrible either. It is also available in pill form but I always try to take the powdered form of amino acids because I don’t necessarily want to ingest any unnecessary additives or the capsule itself.  If you are supplementing with L-Tryptophan it is essential to also supplement with Vitamin B6 (as P5P, which is the activated form of B6) because B6 is necessary for L-tryptophan to make its necessary conversions.  Here is a chewable B6 made by EZ Melts, and here is a pill form by Pure Encapsulations.  B6 also supports healthy metabolism of carbohydrates, fats, and proteins.

Another amino acid that may help with ADHD is L-Tyrosine, especially when used in combination with the 5HTP (from the seeds of an African plant known as Griffonia simplicifolia) but that requires a different post for more detailed information (which I will be writing soon enough).  Please subscribe to get notified of new posts.  (To the right on your desktop and at the bottom of the screen on your cell phone).

If you have any questions or comments, or if you feel it is necessary to correct something that you read here, feel free to do so below. I appreciate any and all of your contributions. If you think this post could help a friend, share it. You just might change their life.

Related posts

Long Term Effects of ADHD Stimulant Medications

Top 6 ADHD Triggers To Nix: Stop Giving THESE to Your Child

8 Amino Acids for ADHD

Top 10 Natural Therapies for ADHD (Coming soon)

Cannabidiol (CBD Oil) for ADHD (Coming soon)

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Ahlin, A., Bejerkenstedt, L., Fernell, E., … (2011). Altered tryptophan and alanine transport in fibroblasts from boys with attention-deficit/hyperactivity disorder (ADHD): an in vitro study. Retrieved from https://behavioralandbrainfunctions.biomedcentral.com/articles/10.1186/1744-9081-7-40

Banjeree, E. and Nandagopal, K. (2015). Does serotonin deficit mediate susceptibility to ADHD? Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/25684070

National Institute on Drug Abuse. (2018). Prescription Stimulants. Retrieved from https://www.drugabuse.gov/publications/drugfacts/prescription-stimulants

U.S. Food and Drug Administration. (2017). Dealing with ADHD: What You Need to Know. Retrieved from https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm269188.htm

WebMD. (2018). ADHD and Substance Abuse. Retrieved from https://www.webmd.com/add-adhd/adhd-and-substance-abuse-is-there-a-link#1

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