5-hydroxytryptophan (5-HTP) is an amino acid. The body makes 5-HTP from tryptophan (an essential amino acid) and converts it to serotonin, an important neurotransmitter (brain chemical). 5-HTP dietary supplements help raise serotonin levels in the brain, which may have a positive effect on the following functions and processes: sleep, mood, anxiety, aggression, appetite, temperature, sexual behavior, and pain sensation.

5-HTP may be helpful in treating a wide variety of conditions related to low serotonin levels, such as the following:

Depression. Scientists believe that low levels of serotonin in the brain cause some forms of depression. Therefore, many of the anti-depressant drugs prescribed for depression increase serotonin levels. 5-HTP is as effective as some antidepressant drugs in treating some individuals with mild to moderate depression, and people treated with 5-HTP have shown improvements in mood, anxiety, insomnia, and physical symptoms.

Fibromyalgia. This is a disorder that causes achy and stiff muscles, tender joints, and ongoing pain at various sites in the body. Although many factors can affect the severity of the disorder, the primary cause of the pain of fibromylagia is low serotonin levels. 5-HTP has been shown to increase pain tolerance, improve sleep quality, and reduce anxiety and depression in patients with fibromyalgia.

Insomnia. 5-HTP has been shown to reduce the time required to fall asleep and to improve sleep quality.

Migraine. 5-HTP reduces the frequency and severity of migraine headaches with fewer side effects than migraine headache drugs.

Obesity. 5-HTP can decrease carbohydrate intake by promoting a feeling of satiety (fullness), and may result in weight loss in overweight individuals.

Headaches in children. Children with headaches associated with sleep disorders can respond favorably to 5-HTP treatment.

5-HTP is extracted from the seed of the African plant Griffonia simplicifolia. It is purified, and concentrated in dietary supplements.

5-HTP is an ingredient in multivitamin and herbal preparations. It is also available as a single ingredient in tablets and capsules. You will find it in doses that include 25 mg, 50 mg, and 100 mg capsules and tablets.

Follow the directions indicated on product packages. Some experts recommend taking 50 to 100 mg of 5-HTP per day for most conditions. Higher doses of 5-HTP are necessary to produce beneficial results in certain conditions. Seek the advice of your health care provider before taking more than 100 mg of 5-HTP per day.

5-HTP causes mild gastrointestinal disturbances in some people. These side effects include mild nausea, heartburn, flatulence, feelings of fullness, and rumbling sensations.

Check with your health care provider before taking 5-HTP if any of the following applies to you:

• You have high blood pressure.
• You are pregnant or nursing.
• You have diabetes.
• You are taking antidepressant drugs, such as monoamine oxidase inhibitors (MAOIs) or selective serotonin reuptake inhibitors (SSRIs), or any other prescription medications.

Seek the advice of your health care provider before giving 5-HTP to children or adolescents.

Taking 5-hydroxytryptophan with carbidopa, a medication used to treat Parkinson's disease, has been associated with side effects, including scleroderma-like illness (the skin becomes hard, thick, and inflamed). Using this combination should be avoided except under the supervision of your healthcare provider.

In addition, 5-HTP should be used with caution, if at all, in people taking selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitors (MAOIs), two types of antidepressant medications. Specifically, the likelihood of developing unpleasant side effects, including serotonin syndrome (characterized by mental status changes, rigidity, hot flashes, rapidly fluctuating vital signs, and possibly coma) is greater if you combine 5-HTP with the drugs sumatriptan, tramadol, trazodone, venlafaxine, and zolpidem.

Angst J, et al. The treatment of depression with L-5-hydroxytryptophan versus imipramine. Results of two open and one double-blind study. Arch Psychiatr Nervenkr. 1977;224:175–186.

Bhatara VS, Magnus RD, Paul KL, et al. Serotonin syndrome induced by venlafaxine and fluoxetine: a case study in polypharmacy and potential pharmacodynamic and pharmacokinetic mechansims. Ann Pharmacother. 1998;32(4):432-436.

Birdsall TC. 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Altern Med Rev. 1998;3:271–280.

Bodner RA, Lynch T, Lewis L, Kahn D. Serotonin syndrome. Neurol. 1995;45(2):219-223.

Byerley WF, et al. 5-Hydroxytryptophan: a review of its antidepressant efficacy and adverse effects. J Clin Psychopharmacol. 1987;7:127–137.

Cangiano C, et al. Effects of oral 5-hydroxy-tryptophan on energy intake and macronutrient selection in non-insulin dependent diabetic patients. Int J Obes Relat Metab Disord. 1998; 22:648–654.

Cangiano C, Ceci F, Cascino A, et al. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. J Clin Nutr. 1992;56:863–867.

Caruso I, Sarzi Puttini P, Cazzola M, et al. Double-blind study of 5-hydroxytryptophan versus placebo in the treatment of primary fibromyalgia syndrome. J Int Med Res. 1990;18:201–209.

Ceci F, Cangiano C, Cairella M, Cascino A, et al. The effects of oral 5-hydroxytryptophan administration on feeding behavior in obese adult female subjects. J Neural Transm. 1989;76:109–117.

DeBenedittis G, Massei R. Serotonin precursors in chronic primary headache. A double-blind cross-over study with L-5-hydroxytryptophan vs. placebo. J Neurosurg Sci. 1985; 29:239–248.

DeGiorgis, G, et al. Headache in association with sleep disorders in children: a psychodiagnostic evaluation and controlled clinical study—L-5-HTP versus placebo. Drugs Exp Clin Res. 1987;13:425–433.

Diamond S, Pepper BJ, Diamond MI, et al. Serotonin syndrome induced by transitioning from phenelzine to venlafaxine: four patient reports. Neurol. 1998;51(1):274-276.

Elko CJ, Burgess JL, Robertson WO. Zolpidem--associated hallucinations and serotonin reuptake inhibition: a possible interaction. J Toxicol Clin Toxicol. 1998;36(3):195-203.

Ganong WF. Review of Medical Physiology. 13th ed. San Mateo, Calif: Appleton & Lange; 1987.

Gardner DM, Lynd LD. Sumatriptan contraindications and the serotonin syndrome. Ann Pharmacother. 1998;32(1):33-38.

George TP, Godleski LS. Possible serotonin syndrome with trazodone addition to fluoxetine. Biol Psychiatry. 1996 Mar;39(5):384-385.

Hernandez AF, Montero MN, Pla A, Villanueva E, et al. Fatal moclobemide overdose or death caused by serotonin syndrome? J Forensic Sci. 1995;40(1):128-130.

Hines Burnham T, et al, eds. Drug Facts and Comparisons 2000. 55th ed. St. Louis, MO:Facts and Comparisons; 2000.

Joffe RT, Sokolov ST. Co-adminstration of fluoxetine and sumatriptan: the Canadian experience. Acta Psychiatr Scand. 1997;95(6):551-552.

Joly P, Lampert A, Thomine E, Lauret P. Development of pseudobullous morphea and sclero-derma-like illness during therapy with L-5-hydroxytryptophan and carbidopa. J Am Acad Dermatol. 1991;25(2):332-333.

Juhl JH. Primary fibromyalgia syndrome and 5-hydroxy-L-tryptophan: a 90-day open study. Altern Med Rev. 1998;3:367–375.

Magnussen I, Nielson-Kudsk F. Bioavailability and related pharmacokinetics in man of orally administered L-5-Hydroxytryptophan in steady state. Acta Pharmacol et Toxicol. 1980;46:257–262.

Martin TG. Serotonin syndrome. Ann Emerg Med. 1996;28:520–526.

Mason BJ, Blackburn KH. Possible serotonin syndrome associated with tramadol and sertraline coadministration. Ann Pharmacother. 1997;31(2):175-177.

Murray MT, Pizzorno JE. Encyclopedia of Natural Medicine. 2nd ed. Rocklin, Calif: Prima Publishing; 1998.

Nicolodi M, Sicuteri F. Fibromyalgia and migraine, two faces of the same mechanism. Serotonin as the common clue for pathogenesis and thearpy. Adv Exp Med Biol. 1996;398:373–379.

Nisijima K, Shimizu M, Abe T, Ishijuro T. A case of serotonin syndrome induced by concomitant treatment with low-dose trazodone and amitriptyline and lithium. Int Clin Psychopharmacol. 1996 Dec;11(4):289-290.

Perry NK. Venlafaxine-induced serotonin syndrome with relapse following amitripyline. Postgrad Med J. 2000;76(894):254.

Puttini PS, Caruso I. Primary fibromyalgia and 5-hydroxy-L-tryptophan: a 90-day open study. J Int Med Res. 1992;20:182–189.

Reeves RR, Bullen JA. Serotonin syndrome produced by paroxetine and low-dose trazodone. Psychosom. 1995 Mar-Apr;36(2):159-160.

Reibring L, Agren H, Hartvig P, et al. Uptake and utilization of [beta-11c] 5-hydroxytryptophan (5-HTP) in human brain studied by positron emission tomography. Pyschiatry Research. 1992;45:215–225.

Shils ME, Olson JA, Shike M, eds. Modern Nutrition in Health and Disease. 8th ed. Media, Pa: Williams & Wilkins; 1994:1.

Spiller HA, Gorman SE, Villalobos D, et al. Prospective multicenter evaluation of tramadol exposure. J Toxicol Clin Toxicol. 1997;35(4):361-364.

Sternberg EM, Van Woert MH, Young SN, et al. Development of a scleroderma-like illness during therapy with L-5-hydroxytryptophan and carbidopa. New Eng J Med. 1980;303:782-787.

Takahashi S, et al. Measurement of 5-hydroxindole compounds during L-5-HTP treatment in depressed patients. Folia Psychiatr Neurol Jpn. 1976;30:461–473.

Toner LC, Tsambiras BM, Catalano G, et al. Central nervous system side effects associated with zolpidem treatment. Clin Neuropharmacol. 2000;23(1):54-58.

Van Hiele LJ. L-5-hydroxytryptophan in depression: the first substitution therapy in psychiatry? Neuropsychobiology. 1980; 6:230–240.

Van Praag HM. Management of depression with serotonin precursors. Biol Psychiatry. 1981;16:291–310.

Zmilacher K, et al. L-5-hydroxytryptophan alone and in combination with a peripheral decarboxylase inhibitor in the treatment of depression. Neuropsychobiology. 1988;20:28–33.