Serotonin metabolism is pellagra.

Altered mental status is common in pellagrins. We evaluated the mental status of pellagrins in relation to the neurohormone, serotonin or 5-hydroxytryptamine (5-HT). Levels of 5-hydroxyindoleacetic acid (5-HIAA), an end product of serotonin in the urine and cerebrospinal fluid (CSF), and of platelet 5-HT were determined in a group of pellagrins and in normal subjects. The results indicated that the 5-HT concentration was reduced in platelets and 5-HIAA excretion in urine was below normal levels. The 5-HIAA concentration in CSF was also reduced, suggesting a decrease in 5-HT functional activity in the brain.