A study published in Archive of Medical Research in 2004 reported that the use of Vit. B6 or Pyridoxine increased the level of 5-htp in blood without supplementing it from outside. This trial concludes that Pyridoxine might increase the metabolism of tryptophan to produce more 5-HTP in intestine.

Arch Med Res. 2004 Jul-Aug; 35(4):271-4.

5-HTP as Free Radical Scavenger:

Hydroxyl radicals are one of the free radicals that produce oxidative damage in the body. 5-htp and melatonin were compared to vitamin C in laboratory for their free radical scavenging antioxidant activity for hydroxyl radical. 5-htp topped the list of the three supplements for anti-hydroxyl radical activity, followed by Vitamin C and then melatonin.

J Pineal Res. 2005 Jan; 38(1):62-6.

5-HTP and Panic Attacks:

Neuropsychologists of at Maastricht University in The Netherlands induced panic attacks in men already suffering with Panic disorder and observed their reactions. The then supplemented half of the subjects with 200 mg of 5-HTP and repeated the experiment. Persons who received 5-HTP supplement displayed diminished response to induction of panic. This trial points toward possibility of inadequacy of serotonin in patients suffering from panic attacks.

In another similar trial, 32 persons were divided into two groups - one received 200 mg 5-HTP and second received only a placebo. CCK-4 (cholecystokinin-tetrapeptide) was used to induce panic attacks in this trial. The results showed that only 19% of the first group was sent into panic attacks by the CCK-4 while panic attacks were induced in 44% of group two.

While not a focus in this trial, subjects who were given 5-htp reported that their panic attacks were less distressing than normal. Another interesting finding was that females in the test reacted more positively to 5-HTP supplementation than males.

Department of Psychiatry, University of Tartu, Raja, Estonia.

J Psychopharmacology. 2004 Jun; 18(2):194-9.