100 mg

60 Enteric Coated Caplets ( SKU: 9288, NPN: 80038036 )


  • Extra-strength 100 mg formula for ease of dosing
  • Naturally sourced from the seed of the African plant Griffonia simplicifolia
  • Unlike L-tryptophan, 5-HTP readily crosses the blood-brain barrier to increase central nervous system synthesis of serotonin1
  • Enteric coated for improved effect and tolerance

Feature Summary

5-HTP (5-hydroxytryptophan) is an amino acid precursor to the brain chemical serotonin, a neurotransmitter essential for balancing mood. Depressive symptoms and mood disturbances have long been associated with low serotonin levels, making 5-HTP an attractive natural option to elevate mood and improve emotional health.

Clinical research supports this hypothesis, with a Cochrane review suggesting that 5-HTP is better than a placebo at alleviating depression.2 In one small study, 73% of people taking 5-HTP experienced significant improvements in depressive symptoms during the eight-week study period.3 The participants in this study began by taking 50 mg three times daily for two weeks, then 100 mg three times daily for two weeks, then 133 mg three times daily for the remaining four weeks of the study.

5-HTP has also been used to address serotonin imbalance implicated in chronic pain conditions including migraines, as well in fibromyalgia and insomnia. People with fibromyalgia who take 300–400 mg of 5-HTP daily in divided doses have reported improvements in symptoms, including pain severity, morning stiffness, and sleeplessness.4,5,6 5-HTP is known to increase sleep quality, which is critical in those suffering from depression or fibromyalgia. In fact, 5-HTP is known to promote and maintain sleep in healthy adults, as well as those experiencing insomnia.7Supplementation of 5-HTP has been associated with improved sleep continuity and sleep quality, at least in part by reducing the incidence of premature REM sleep onset (shortened REM latency).8,9

Medicinal Ingredients

Each Caplet Contains:
L-5-Hydroxytryptophan (Griffonia simplicifolia) (seed) 100 mg

Non-Medicinal Ingredients

Dibasic calcium phosphate dihydrate, purified water, microcrystalline cellulose, enteric coating (purified water, ethylcellulose, medium chain triglycerides, oleic acid, carbohydrate gum [cellulose], glycerin, sodium alginate, stearic acid), vegetable grade magnesium stearate (lubricant).


Contains no artificial colours, preservatives, or sweeteners; no dairy, starch, sugar, wheat, gluten,yeast, soy, corn, egg, fish, shellfish, animal products,salt, tree nuts, or GMOs. Suitable for vegetarians/vegans.


Do not use if you have scleroderma.

Drug Interactions

Combining serotonergic drugs such as antidepressants, dextromethorphan (in cough syrups), meperidine (Demerol), tramadol, and others may increase the risk of serotonergic side effects such as serotonin syndrome.10 Combining 5-HTP and carbidopa-levodopa (Sinement®) can increase the risk of serotonergic side effects. Carbidopa is sometimes intentionally used with 5-HTP to minimize peripheral 5-HTP metabolism and boost the amount that reaches the brain. But this combination might increase the risk of some side effects including hypomania, restlessness, rapid speech, anxiety, insomnia, and aggressiveness, as well as scleroderma-like skin reactions.11,12 Individuals using this drug combination should be monitored by a health care practitioner. Anecdotally, 5-HTP may lower blood pressure and could be additive to antihypertensive drugs.

  1. Birdsall, T.C. (1998). 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Alternative Medicine Review, 3(4), 271-280.
  2. Shaw, K. A., Turner, J., &Del Mar, C. (2002). Tryptophan and 5-hydroxytryptophan for depression. Cochrane Database Systematic Review, (1), CD003198.
  3. Jangid, P., Malik, P., Singh, P., et al. (2013). Comparative study of efficacy of l-5-hydroxytryptophan and fluoxetine in patients presenting with first depressive episode. Asian Journal of Psychiatry, 6(1), 29-34.
  4. Nicolodi, M., &Sicuteri, F. (1996). Fibromyalgia and migraine, two faces of the same mechanism. Serotonin as the common clue for pathogenesis and therapy. Advances in Experimental Medicine and Biology, 398, 373-379.
  5. Caruso, I., Sarzi Puttini, P., Cazzola, M., et al. (1990). Double-blind study of 5-hydroxytryptophan versus placebo in the treatment of primary fibromyalgia syndrome. Journal of International Medical Research, 18(3), 201-209.
  6. Sarzi Puttini, P. &Caruso, I. (1992). Primary fibromyalgia syndrome and 5-hydroxy-L-tryptophan: a 90-day open study. Journal of International Medical Research, 20(2), 182-189.
  7. Wyatt, R.J., Zarcone, V., Engelman, K., et al. (1971). Effects of 5-hydroxytryptophan on the sleep of normal human subjects. Electroencephalography and Clinical Neurophysiology, 30(6), 505-509.
  8. Harris, C.D. (2005). Neurophysiology of sleep and wakefulness. Respiratory Care Clinics of North America, 11(4), 567-586.
  9. Riemann, D., Hohagen, F., Fritsch-Montero, R., et al. (1992). Cholinergic and noradrenergic neurotransmission: impact on REM sleep regulation in healthy subjects and depressed patients. Acta Psychiatrica Belgica, 92(3), 151-171.
  10. Singhal, A.B., Caviness, V.S., Begleiter, A.F., et al. (2002). Cerebral vasoconstriction and stroke after use of serotonergic drugs. Neurology, 58(1), 130-133.
  11. Sternberg, E.M., Van Woert, M.H., Young, S.N., et al. (1980). Development of a scleroderma-like illness during therapy with L-5-hydroxytryptophan and carbidopa. New England Journal of Medicine, 303(14), 782-787.
  12. Joly, P., Lampert, A., Thomine, E., et al. (1991). Development of pseudobullous morphea and scleroderma-like illness during therapy with L-5-hydroxytryptophan and carbidopa. Journal of the American Academy of Dermatology, 25(2 Pt 1), 332-333.