What is it?
5-HTP is used for depression, anxiety, and many other conditions, but there is no good scientific evidence to support most of these uses.
How effective is it?
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.
The effectiveness ratings for 5-HTP are as follows:
Possibly effective for...
- Depression. Taking 5-HTP by mouth seems to improve symptoms of depression in some people. Some clinical research shows that 5-HTP might work as well as some prescription antidepressant drugs for improving depression symptoms. In most studies, 150-800 mg daily of 5-HTP was taken.
Possibly ineffective for...
- Down syndrome. Most research shows that 5-HTP does not improve muscle strength or development when given to children with Down syndrome from infancy until 3-4 years of age.
Insufficient evidence to rate effectiveness for...
- A type of anxiety marked by recurrent thoughts and repetitive behaviors (obsessive-compulsive disorder or OCD). Early research shows that taking 5-HTP with the antidepressant drug fluoxetine (Prozac) for 12 weeks may improve some symptoms of OCD.
- Anxiety. Early research shows that taking 25-150 mg of 5-HTP by mouth daily along with carbidopa seems to reduce anxiety symptoms in people with anxiety disorders. But other early research shows that taking higher doses of 5-HTP, 225 mg daily or more, seems to make anxiety worse.
- Brain damage that affects muscle movement (cerebellar ataxia). Evidence on the use of 5-HTP for cerebellar ataxia is unclear. Early evidence shows that taking 5 mg/kg of 5-HTP daily for 4 months can decrease nervous system dysfunction. However, other research shows that taking 5-HTP daily for up to one year does not improve symptoms of cerebellar ataxia.
- Fibromyalgia. Early research suggests that taking 100 mg of 5-HTP by mouth three times daily might improve pain, tenderness, sleep, anxiety, fatigue, and morning stiffness in people with fibromyalgia.
- Symptoms of menopause. Early research suggests that taking 150 mg of 5-HTP daily for 4 weeks does not reduce hot flashes in postmenopausal adults.
- Migraine. Some studies show that taking 5-HTP daily does not reduce migraines. But other studies show that it might be as beneficial as prescription drugs for adults. 5-HTP does not seem to reduce migraines in children.
- Obesity. Early research suggests that taking 5-HTP might help reduce appetite, caloric intake, and weight in people who are obese. Other research suggests that using a specific mouth spray containing 5-HTP and other extracts for 4 weeks increases weight loss by about 41% in overweight postmenopausal adults.
- A type of anxiety marked by episodes of intense fear (panic disorder). Early research shows that receiving 60 mg of 5-HTP daily by IV does not reduce anxiety in people with panic disorders.
- Parkinson disease. Early research shows that taking 100-150 mg of 5-HTP by mouth daily with conventional drugs seems to reduce shaking, but these benefits only continue for up to 5 months. Other early research shows that taking 50 mg of 5-HTP daily might reduce symptoms of movement disorders from the drug levodopa, as well as symptoms of depression, in people with Parkinson disease. But taking larger doses of 5-HTP, 275-1500 mg daily, along with carbidopa might worsen some symptoms.
- Tension headache. Early research suggests that taking 100 mg of 5-HTP three times daily for 8 weeks does not reduce pain or the length of tension headaches.
- Alcohol use disorder.
- Alzheimer disease.
- Attention deficit-hyperactivity disorder (ADHD).
- Premenstrual syndrome (PMS).
- Withdrawal from heroin, morphine, and other opioid drugs.
- Other conditions.
How does it work?
Are there safety concerns?
Other potential side effects of 5-HTP include heartburn, stomach pain, nausea, vomiting, diarrhea, drowsiness, sexual problems, and muscle problems.
5-HTP is POSSIBLY UNSAFE when taken by mouth in large doses. Doses from 6-10 grams daily have been linked to severe stomach problems and muscle spasms.
Special precautions & warnings:Pregnancy and breast-feeding: There isn't enough reliable information to know if 5-HTP is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.
Children: 5-HTP is POSSIBLY SAFE when taken by mouth appropriately. Doses of up to 5 mg/kg daily have been used safely for up to 3 years in infants and children up to 12-years-old. As with adults, there is also concern about the potential for eosinophilia-myalgia syndrome (EMS) in children, a serious condition involving extreme muscle tenderness (myalgia) and blood abnormalities (eosinophilia).
Surgery: 5-HTP can affect a brain chemical called serotonin. Some drugs administered during surgery can also affect serotonin. Taking 5-HTP before surgery might cause too much serotonin in the brain and can result in serious side effects including heart problems, shivering, and anxiety. Tell patients to stop taking 5-HTP at least 2 weeks before surgery.
Are there interactions with medications?
- Carbidopa (Lodosyn)
- 5-HTP can affect the brain. Carbidopa (Lodosyn) can also affect the brain. Taking 5-HTP along with carbidopa can increase the risk of serious side effects including rapid speech, anxiety, aggressiveness, and others.
- Sedative medications (CNS depressants)
- 5-HTP might cause sleepiness and drowsiness. Medications that cause sleepiness are called sedatives. Taking 5-HTP along with sedative medications might cause too much sleepiness.
Some sedative medications include clonazepam (Klonopin), lorazepam (Ativan), phenobarbital (Donnatal), zolpidem (Ambien), and others.
- Serotonergic drugs
- 5-HTP can increase a chemical in the brain called serotonin. Some medications also increase serotonin. Taking 5-HTP along with these medications might increase serotonin too much. This can cause serious side effects including severe headache, heart problems, shivering, confusion, and anxiety.
Some of these medications include fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft), amitriptyline (Elavil), clomipramine (Anafranil), imipramine (Tofranil), sumatriptan (Imitrex), zolmitriptan (Zomig), rizatriptan (Maxalt), methadone (Dolophine), tramadol (Ultram), and many others.
Are there interactions with herbs and supplements?
- Herbs and supplements with sedative properties
- 5-HTP can cause sleepiness or drowsiness. Using it along with other herbs and supplements that have the same effect might cause too much sleepiness. Some of these herbs and supplements include calamus, California poppy, catnip, hops, Jamaican dogwood, kava, St. John's wort, skullcap, valerian, yerba mansa, and others.
- Herbs and supplements with serotonergic properties
- 5-HTP increases a brain chemical called serotonin. Taking 5-HTP along with other herbs and supplements that increase serotonin might lead to too much serotonin and cause side effects including heart problems, shivering and anxiety. Other herbs and supplements that increase serotonin levels include Hawaiian baby woodrose, L-tryptophan, S-adenosylmethionine (SAMe), and St. John's wort.
Are there interactions with foods?
- There are no known interactions with foods.
What dose is used?
- For depression: Most commonly, 150-800 mg daily is taken for 2-6 weeks. These doses are sometimes divided up and administered as 50 mg to 100 mg three times a day. Sometimes the dose starts out low and steadily increases every 1-2 weeks until a target dose is reached. Less commonly, higher doses are used. In one study, the dose is steadily increased up to 3 grams per day.
To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.
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