the biological treatment of depression includes administration of psychoactive drugs ( cyclic antidepressants , mao-inhibitors , neuroleptics and lithium ) , use of certain substances which in small amounts are normally present in food such as , l-tryptophan ( l-tp ) and l-5-hydroxytryptophan ( l-5htp ) , electroconvulsive therapy ( ect ) and various manipulations of the sleep-wake rhythms .
C0041249
l-tryptophan
C0000578
l-5-hydroxytryptophan