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

Depression - Low levels of serotonin in the brain can contribute to the development of depression. Many drugs prescribed for depression increase serotonin levels. Some studies indicate that 5-HTP may be as effective as certain antidepressant drugs in treating individuals with mild to moderate depression.
Such individuals have shown improvements in mood, anxiety, insomnia, and physical symptoms.

Fibromyalgia - 5-HTP has been shown to improve sleep quality and reduce pain, stiffness, anxiety, and depression in individuals with fibromyalgia.
Insomnia - Medical research indicates that supplementation with tryptophan before bedtime can induce sleepiness and delay wake times. Studies also suggest that 5-HTP may be useful in treating insomnia associated with depression.

Headaches - Some studies suggest that 5-HTP may be effective in children and adults with various types of headaches including migraines.

Obesity - There is some evidence that low tryptophan levels may contribute to excess fat and carbohydrate intake.

Doses
Some studies have used dosages of 300 mg a day for depression but any dose above 100 mg to be high. Most products are sold in 50 and 100 mg capsules. Some people do well with 20 to 50 mg, while others may temporarily require 100 mg or more. Those who do well with small doses can open a capsule by pulling on each end and take a portion mixed with water. 5-HTP is best absorbed on an empty stomach. Some users have tried taking a smaller amount sublingually, that is, under the tongue.

Possible Side effects / Precautions / Possible Interactions:
There is concern that it can cause a serious side effect called eosinophilia myalgia syndrome. Some people think this side effect is only caused by a contaminant in some 5-HTP products; but there is not enough scientific evidence to know if it is caused by 5-HTP, a contaminant, or some other factor. Until more is known, 5-HTP should be avoided.

Other potential side effects of 5-HTP include heartburn, stomach pain, nausea, vomiting, diarrhea, drowsiness, sexual problems, and muscle problems.

Special Precautions & Warnings:
Pregnancy and breast-feeding: 5-HTP is POSSIBLY UNSAFE in pregnancy and breast-feeding. Avoid using it.

Down syndrome: There are reports of 5-HTP causing seizures in some people with Down syndrome. In one group studied, 15% of people with Down syndrome receiving long-term 5-HTP treatment experienced seizures.

Interactions:
Medications for depression (Antidepressant drugs) interacts with 5-HTP
5-HTP increases a brain chemical called serotonin. Some medications for depression also increase serotonin. Taking 5-HTP along with these medications for depression might increase serotonin too much and cause serious side effects including heart problems, shivering, and anxiety. Do not take 5-HTP if you are taking medications for depression.

Some of these medications for depression include fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft), amitriptyline (Elavil), clomipramine (Anafranil), imipramine (Tofranil), and others.

Medications for depression (MAOIs) interacts with 5-HTP
5-HTP increases a chemical in the brain. This chemical is called serotonin. Some medications used for depression also increase serotonin. Taking 5-HTP with these medications used for depression might cause there to be too much serotonin. This could cause serious side effects including heart problems, shivering, and anxiety.

Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.

Carbidopa (Lodosyn) interacts with 5-HTP
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.

Dextromethorphan (Robitussin DM, and others) interacts with 5-HTP
5-HTP can affect a brain chemical called serotonin. Dextromethorphan (Robitussin DM, others) can also affect serotonin. Taking 5-HTP along with dextromethorphan (Robitussin DM, others) might cause too much serotonin in the brain and serious side effects including heart problems, shivering, and anxiety. Do not take 5-HTP if you are taking dextromethorphan (Robitussin DM, and others).

Meperidine (Demerol) interacts with 5-HTP

5-HTP increases a chemical in the brain called serotonin. Meperidine (Demerol) can also increase serotonin in the brain. Taking 5-HTP along with meperidine (Demerol) might cause too much serotonin in the brain and serious side effects including heart problems, shivering, and anxiety.

Tramadol (Ultram) interacts with 5-HTP
Tramadol (Ultram) can affect a chemical in the brain called serotonin. 5-HTP can also affect serotonin. Taking 5-HTP along with tramadol (Ultram) might cause too much serotonin in the brain and side effects including confusion, shivering, stiff muscles, and others.

Research studies / References