5-hydroxytryptophan (5-HTP) and the “feel good” neurotransmitter serotonin

Are you a healthcare provider? Read our research summary of 5-HTP on Naturopathic Pediatrics PRO, our website for professionals.

What is 5-HTP? A Parent-Friendly Guide

5-hydroxytryptophan (5-HTP) is a naturally occurring compound that the body makes from tryptophan, an amino acid found in food. After conversion to 5-HTP, it is further transformed into serotonin—a neurotransmitter involved in mood, sleep, appetite, digestion, cognition, and more. Often referred to as the “feel-good” neurotransmitter, serotonin is critical for emotional balance, focus, impulse control, and a sense of wellbeing.

Many individuals—both children and adults—may have difficulty producing adequate serotonin due to poor conversion of tryptophan to 5-HTP, especially in the presence of vitamin B6 deficiency. Supplemental 5-HTP bypasses this rate-limiting step, increasing serotonin availability more directly.

5-HTP, Serotonin, and Melatonin: A Metabolic Pathway

The journey begins with dietary tryptophan, which converts to 5-HTP via the enzyme tryptophan hydroxylase. 5-HTP then crosses the blood-brain barrier and is converted into serotonin by the enzyme DOPA decarboxylase. Serotonin, in turn, can be transformed into melatonin—the hormone that regulates sleep cycles—via a sequence of enzymatic reactions. Excess serotonin and 5-HTP are metabolized by the liver and excreted in the urine.

SSRIs vs. 5-HTP: What’s the Difference?

Selective serotonin reuptake inhibitors (SSRIs) are antidepressants that work by blocking the reabsorption (reuptake) of serotonin, making more of it available in the brain. In contrast, 5-HTP increases serotonin production by providing the body with more of its raw material. While SSRIs retain existing serotonin in the brain, 5-HTP helps create more. Some practitioners use 5-HTP as part of a transition away from SSRIs or, in some cases, as a standalone alternative.

Is There an RDA for 5-HTP?

There is no established Recommended Daily Allowance (RDA) for 5-HTP, as it is not found in food. However, clinical studies in adults have used doses ranging from 50 mg to 800 mg per day.

Food Sources and the Role of Griffonia simplicifolia

While 5-HTP is not found in food, its precursor—tryptophan—is present in many protein-rich foods such as turkey, eggs, milk, nuts, bananas, and spinach. Supplemental 5-HTP is typically derived from the seeds of an African plant called Griffonia simplicifolia.

Deficiency and Its Impact

Low serotonin levels can result from poor production or poor utilization. This may lead to symptoms such as depression, anxiety, insomnia, weight gain, slow digestion, OCD, or panic disorders. Supplemental 5-HTP may help support serotonin production and improve these symptoms—especially in individuals with low tryptophan intake or B6 deficiency.

Safety and Supplementation Considerations

5-HTP may cause side effects like nausea, diarrhea, and increased satiety when taken in high doses. More concerning is the potential for serotonin syndrome, particularly in combination with SSRIs or other serotonergic agents. Symptoms include agitation, confusion, muscle twitching, and high blood pressure—and in severe cases, seizures or coma.

Use caution in individuals with liver disease, high blood pressure, diabetes, or those who are pregnant or breastfeeding. Always consult a healthcare provider before using 5-HTP, especially in children.

Pediatric Research: What Do We Know?

Autism Spectrum Disorder (ASD)

Several studies associate serotonin imbalance with ASD. Children with autism often show either elevated serotonin in blood or low serotonin binding capacity in the brain. 5-HTP could theoretically support serotonin synthesis in this population, though evidence for its use remains limited.

Sleep Terrors

One small study found that 5-HTP reduced the frequency of sleep terrors in children by promoting REM sleep and improving sleep architecture. However, in some children, increasing serotonin may worsen vivid dreams or sleep disruptions.

ADHD

Alterations in tryptophan metabolism have been noted in children with ADHD, though the role of 5-HTP is still speculative. More research is needed before it can be recommended.

Other Conditions

In adults, 5-HTP has shown benefit in conditions like depression, anxiety, migraines, obesity, and even social cognition. One study linked 5-HTP with improved impulse control and reduced aggression—potentially relevant for some children.

Is It Safe in Children?

Safety studies on 5-HTP in children are sparse. A cautious approach may involve starting with 1 mg/kg/day, increasing to 2.5 mg/kg/day only if well-tolerated. Communication is key—children must be able to describe symptoms such as vivid dreams or agitation. Children with MAOA or COMT SNPs may have paradoxical responses to 5-HTP and should be monitored closely.

In my practice, I use 5-HTP lozenges with school-age and adolescent children who are verbal and can self-assess. I’ve found that some children quickly recognize whether a supplement helps or worsens their symptoms.

Clinical Pearls

• Combine 5-HTP with P5P (active B6) for optimal conversion to serotonin.
• Avoid in children with vivid dreams, sleep terrors, or extreme emotional sensitivity.
• Consider as an adjunct or alternative to SSRIs under supervision.
• Always assess for early signs of serotonin excess.

Summary

5-HTP is a direct precursor to serotonin and can support mood, sleep, and neurological health. While adult research is robust, pediatric research is still emerging. Supplementation should be approached with caution, especially in children, and always under professional supervision.

Disclaimer: This article is for informational purposes only. It is not a substitute for professional medical advice. Always consult your or your child’s healthcare provider before starting any new supplement, including 5-HTP.

References:

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