Enjoy an active lifestyle? Why not add 5-HTP to your pre-bed routine? 5-HTP (5-hydroxytryptophan) is made in the body from tryptophan and is a precursor to the production of serotonin; a natural neurotransmitter. Each of these premium capsules from Swanson Health has 100mg of 5-HTP. Enjoy an active lifestyle? Why not add 5-HTP to your pre-bed routine? 5-HTP (5-hydroxytryptophan) is made in the body from tryptophan and is a precursor to the production of serotonin; a natural neurotransmitter. Each of these premium capsules from Swanson Health has 100mg of 5-HTP. 100mg of 5-HTP per capsule. A natural precursor to serotonin. Consume pre-bed as part of an active lifestyle. 60 capsules per pack 5-HTP is a compound that the body makes from the essential amino acid Tryptophan. Whilst Tryptophan is typically obtained from meat, fish and dairy, there are no dietary sources of 5-HTP. Supplemental 5-HTP is obtained from the seeds of the Griffonia simplicifolia shrub. 5-HTP is a food supplement from the seeds of Griffonia simplicifolia, a West African shrub. Curious about this supplement?