Last Updated: January 24 2022

5-HTP is the precursor to serotonin, the neurotransmitter sometimes touted to be responsible for happiness. 5-HTP is a simple way to increase brain serotonin levels by bypassing the rate-limiting step, and users reap either the rewards or the hazards of increased brain serotonin.

5-HTP is most often used for


5-HTP is a compound which gets converted into serotonin in the brain. Serotonin is one of the principal neurotransmitters involved in happiness and anti-depression.

5-HTP has been used with success to restore serotonin levels in those that may suffer from decreased serotonin levels, such as the depressed and those with high levels of body inflammation (typically seen in metabolic syndrome).

What else is 5-HTP known as?
Note that 5-HTP is also known as:
  • 5-hydroxytryptophan
  • serotonin precursor
Dosage information

A typical dose of 5-HTP is in the range of 300-500 mg, taken either once daily or in divided doses. Lower doses may also be effective, although usually when paired with other substances.

For the purpose of reducing food intake, 5-HTP should be taken with a meal as it increases satiety from food intake (rather than reducing appetite/hunger).

5-HTP should not be taken with any neurological drug that has been prescribed for antidepressant or other cognitive purposes unless cleared by a medical doctor. This is most important for SSRI usage, wherein the combination with 5-HTP is potentially lethal.

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