Related Terms
- 5-Hydroxytroptophan, Griffonia plant seed extract, Griffonia simplicifolia, L-5-HTP, L-5-hydroxytroptophan, Natrol® 5-HTP, Natural Factors® 5-HTP, oxitriptan, serotonin, Tript-OH®, tryptophan.
- Select combination products: Gabadone™ (5-HTP, tryptophan, and other amino acids), Nature's Way 5-HTP (5-HTP, vitamin B6, vitamin C), Natural Factors® Tranquil Sleep (5-HTP, melatonin, L-theanine).
- Note: 5-HTP should not to be confused with L-tryptophan.
Background
- 5-HTP is the precursor of the neurotransmitter serotonin. Commercially available 5-HTP is obtained from the seeds of the plant Griffonia simplicifolia.
- 5-HTP has been suggested as a treatment for many conditions. Some research supports the use of 5-HTP in treating cerebellar ataxia, headache, depression, psychiatric disorders, and fibromyalgia, and as an appetite suppressant or weight loss agent. There is insufficient scientific evidence to support the use of 5-HTP for any other medical condition.
- 5-HTP may cause gastrointestinal disturbances, mood disturbances, seizure, or abnormal blood counts. Some side effects might result from contaminants in 5-HTP products.
Scientific Evidence
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Cerebellar ataxia
5-HTP has been observed to have benefits in some people who have difficulty standing or walking because of cerebellar ataxia. However, current evidence is mixed.
Grade: B
Obesity
Studies suggest that 5-HTP may reduce eating behaviors, lessen caloric intake, and promote weight loss in obese individuals.
Grade: B
Alcoholism (withdrawal symptoms)
Early research suggests that 5-HTP may lessen alcohol withdrawal symptoms. Further research is needed before a conclusion can be made.
Grade: C
Anxiety
Although 5-HTP has been proposed as a possible treatment for anxiety disorders, sufficient human evidence to make a firm conclusion is lacking.
Grade: C
Depression
The results of numerous studies in humans suggest that 5-HTP may aid in the treatment of depression. However, it is not known whether 5-HTP is as effective as commonly prescribed antidepressant drugs.
Grade: C
Down's syndrome
Preliminary research on 5-HTP in children with Down's syndrome has yielded insignificant results. Further research is necessary.
Grade: C
Fibromyalgia
There is a small amount of research evaluating the use of 5-HTP for fibromyalgia. Early evidence suggests that 5-HTP may reduce the number of tender points, anxiety, and the intensity of pain, and may improve sleep, fatigue, and morning stiffness. Further research is needed before a conclusion can be made.
Grade: C
Headache
Several studies, in both children and adults, suggest that 5-HTP may be effective in reducing the severity and frequency of headaches, including tension headaches and migraines. Further research is needed.
Grade: C
Mood
In early research, 5-HTP lacked an effect on mood in healthy, young subjects. However, in this population, 5-HTP may impair decision-making. Further well-designed research is needed.
Grade: C
Neurologic disorders
5-HTP has been studied in panic disorder and various neurologic disorders. Additional clinical research is needed before conclusions can be made.
Grade: C
Parkinson's disease
Parkinson's disease is a neurological disorder that usually develops around the age of 50. The disorder occurs when the brain cells that make dopamine slowly degenerate. Symptoms include tremors (shaking) and difficulties with movement and coordination. 5-HTP has been studied, usually in combination with drugs, for Parkinson's disease.
Grade: C
Psychiatric disorders
It has been suggested that 5-HTP may reduce psychotic symptoms and mania in panic disorder, but studies in people with schizophrenia have shown mixed results.
Grade: C
Sleep disorders
Insufficient evidence is currently available regarding the use of 5-HTP for sleep disorders. Additional studies are needed before a conclusion can be drawn.
Grade: C
Hot flashes
Limited research suggests that 5-HTP may be ineffective for reducing hot flash frequency in postmenopausal women. Further research is required before firm conclusions can be drawn.
Grade: D
Seizures/epilepsy (myoclonic disorders)
Although 5-HTP has been studied as a treatment for various myoclonic syndromes and epilepsy, available research does not support the use of 5-HTP for these conditions.
Grade: D
*Click here for more information on the Natural Standard grading system.
Tradition/Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.
- Aggression, agoraphobia, Alzheimer's disease, amyotrophic lateral sclerosis (ALS), anorexia, antioxidant, appetite suppressant, attention-deficit hyperactivity disorder (ADHD), autism, bulimia nervosa, cough, deficiency (aromatic L-amino acid decarboxylase deficiency, serotonin deficiency), delirium tremens (DTs), diabetes, digestion, dizziness, dystonia (muscle contraction disorder), eating disorders (binge eating), endocrine disorders (Cushing's syndrome, hypothalamic syndrome), eye disorders (ophthalmoplegia), gastroesophageal reflux disease (GERD), gynecological disorders (premenstrual dysphoria), hepatitis, herpes virus infection (Ramsay Hunt syndrome), hormonal disorders, inflammation, melatonin deficiency, migraines, mood disorder, myoclonic disorders (Lance-Adams syndrome), pain, phenylketonuria, premenstrual syndrome, psychosis (LSD-induced), relaxation, restless leg syndrome, seasonal affective disorder, sexual dysfunction, stress, temperature regulation.
Dosing
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (18 years and older)
- For cerebellar ataxia, 10–16 milligrams per kilogram of body weight has been taken by mouth daily.
- For depression, 200–300 milligrams has been taken by mouth daily.
- For fibromyalgia, 100 milligrams has been taken by mouth three times daily.
- For headache, 300–600 milligrams has been taken by mouth daily in divided doses.
- For hot flashes, 150 milligrams has been taken by mouth daily for four weeks.
- For mood, 50 milligrams has been taken by mouth in two separate doses.
- For obesity, 8 milligrams per kilogram of body weight or 750–900 milligrams has been taken by mouth daily.
- For psychiatric disorders, 25–350 milligrams has been taken by mouth daily for anxiety.
- For seizures or epilepsy (myoclonic disorders), 15 milligrams per kilogram of body weight has been taken by mouth daily, in combination with carbidopa, for 14 days to one month.
- For sleep disorders, 100 milligrams has been taken by mouth at 7:30 p.m., followed by 200 milligrams at 9:00 p.m. for 5 nights.
Children (younger than 18 years)
- 5-HTP may be unsafe in this population, due to potential side effects.
- For Down syndrome, newborns have been given two milligrams per kilogram of body weight by mouth daily.
- For headache, up to 150 milligrams has been taken by mouth daily for 12 weeks.
- For sleep disorders, infants with Down syndrome have been given varying doses (based on age and tolerance) for 12-36 months. Schizophrenic boys (aged seven and nine years) have been given three milligrams per kilogram of body weight by mouth for eight days.
Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Allergies
- Avoid in individuals with a known allergy or hypersensitivity to 5-HTP. Signs of allergy may include rash, itching, or shortness of breath.
Side Effects and Warnings
- In light of the concern related to eosinophilia myalgia syndrome (EMS), use of 5-HTP should be supervised by a qualified healthcare provider.
- 5-HTP may cause abdominal pain, absence of menstrual bleeding, agitation, aggressiveness, anorexia, anxiety, depressed mood, diarrhea, dizziness, drowsiness, ear buzzing, eosinophilia, eosinophilia myalgia syndrome (EMS), euphoria, fatigue, gas, gastrointestinal side effects, hand wringing, headache, heartburn, hives, hypomania, impaired decision-making, increased appetite, increased blood cortisol or kynurenine, irritability, loss of inhibition, lowered blood pressure, lowered cholesterol, mania, muscle pain or weakness or breakdown, nausea, pacing, palpitations, psychic hyperkinetic syndrome, rapid speech, restlessness, seizure, scleroderma-like symptoms, sleep changes, slowed heart rate, sodium retention, strong muscle contractions, sweating, taste changes, vertigo, vivid dreams, vomiting, or weight gain.
- Use cautiously in patients with existing gastrointestinal disorders, as 5-HTP may cause worsening of symptoms.
- Use cautiously in patients with schizophrenia, due to the potential for worsening symptoms.
- Use cautiously in patients with HIV/AIDS, particularly HIV-1 infection.
- Use cautiously in patients with seizure disorders or those using agents that may lower the seizure threshold, due to increased risk of seizures.
- Use cautiously in patients with a history of mental disorders.
- Use cautiously in patients using CNS depressants. Drowsiness or sedation may occur. Use caution if driving or operating heavy machinery.
- Use cautiously in patients taking decarboxylase inhibitors.
- 5-HTP may cause low blood pressure. Caution is advised in patients taking drugs, herbs, or supplements that lower blood pressure.
- Use cautiously in patients with bradycardia (slow heart rate).
- Avoid in patients with eosinophilia syndromes, due to cases of eosinophilia and eosinophilia-myalgia syndrome (EMS).
- Avoid in infants with Down syndrome, due to the potential for spasm.
- Avoid in patients with mitochondrial encephalomyopathy.
- Avoid in patients with suicidal thoughts, based on suicide attempts following 5-HTP use.
- Avoid use in individuals using "party pills" (benzylpiperazine and trifluoromethylphenylpiperazine), based on population studies suggesting that the combination is associated with increased adverse effects from the party pills.
- Avoid in patients taking antidepressant medications (tricyclics [TCAs], monoamine oxidase inhibitors [MAOIs], selective serotonin reuptake inhibitors [SSRIs], nefazodone, trazodone, venlafaxine, mirtazapine, or bupropion) or any other medications that may affect serotonin, due to potential increases in serotonin levels and increased risk of serotonin toxicity syndrome.
- Avoid in women who are pregnant or lactating, due to a lack of safety data.
- Avoid in patients with a known allergy to 5-HTP-containing products. Signs of allergy to 5-HTP may include rash, itching, or shortness of breath.
Pregnancy and Breastfeeding
Avoid in pregnant or breastfeeding women, due to a lack of available scientific evidence. 5-HTP products may contain contaminants or increase levels of prolactin, a hormone needed for milk production.
Interactions
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
Note: 5-HTP is a precursor to serotonin; thus, it may interact with agents that modulate levels of serotonin.
- 5-HTP may cause low blood pressure. Caution is advised in patients taking drugs that lower blood pressure.
- 5-HTP may interfere with the way the body processes certain drugs using the liver's cytochrome P450 enzyme system. As a result, the levels of these drugs may be increased or decreased in the blood, and may cause increased or decreased effects or potentially serious adverse reactions. Patients using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.
- 5-HTP may increase the amount of drowsiness caused by some drugs. Examples include benzodiazepines such as lorazepam (Ativan®) or diazepam (Valium®), barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, and alcohol. Caution is advised while driving or operating machinery.
- 5-HTP may interact with angiotensin-converting enzyme receptor blockers (ARBs), antianxiety agents (such as buspirone and trazodone), anticancer agents, antidepressants (including monoamine oxidase inhibitors [MAOIs] such as L-deprenyl, selective serotonin reuptake inhibitors [SSRIs], serotonin and norepinephrine reuptake inhibitors [SNRIs] such as venlafaxine, tetracyclics such as mirtazapine, or tricyclics [TCAs]), anti-inflammatories, antiobesity agents (such as phentermine), antiseizure agents, antipsychotic agents (such as haloperidol), barbiturates (such as pentobarbital), benzodiazepines, benzylpiperazine, cannabinoids (such as tetrahydrocannabinol), cholesterol-lowering agents, CNS depressants, decarboxylase inhibitors (such as carbidopa and benserazide), diltiazem, drugs that lower seizure threshold, growth hormones, hormonal agents, lithium carbonate, losartan, methamphetamine, metoclopramide, painkillers, sedatives, serotonin receptor antagonists (such as methysergide, nefazodone, cyproheptadine, and ritanserin), or thyroid hormones.
Interactions with Herbs and Dietary Supplements
- 5-HTP may cause low blood pressure. Caution is advised in patients taking herbs or supplements that lower blood pressure.
- 5-HTP may interfere with the way the body processes certain herbs or supplements using the liver's cytochrome P450 enzyme system. As a result, the levels of other herbs or supplements may become too high or too low in the blood. It may also alter the effects that other herbs or supplements possibly have on the P450 system.
- 5-HTP may increase the amount of drowsiness caused by some herbs or supplements.
- 5-HTP may interact with Alpinia zerumbet, antianxiety agents (such as St. John's wort), anticancer agents, antidepressants (including monoamine oxidase inhibitors [MAOIs] and selective serotonin reuptake inhibitors [SSRIs]), anti-inflammatories, antiobesity agents, antioxidants, antiseizure agents, antipsychotics, cannabinoids, cholesterol-lowering agents, chromium, herbs that lower the seizure threshold, hormonal herbs and supplements, jujubosides from Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H.F.Chow, L-tyrosine, magnesium, melatonin, niacin, painkillers, protein, SAMe, sedatives, serotonin receptor antagonists, spinosin, theanine, thyroid herbs and supplements, tryptophan, tryptophan-containing foods, or vitamin B6.
