To the Editor:— One of the projects at Rockland State Hospital has been an investigation of the effect of certain psychopharmaceuticals on the endocrine system of schizophrenics. During the course of this project, one of the normal control subjects for semen studies (a 47-year-old white man) became moderately depressed and was placed on phenelzine sulfate (Nardil), supplied by Warner-Lambert Products, 15 mg. q.i.d. A marked relief of the depression was apparent at the end of 3 weeks. Equally striking, however, was the improvement in his semen; the sperm count suddenly increased one month after the start of treatment from a baseline of about 60 million per cc. to over 100 million per cc., with just as remarkable a qualitative improvement in motility and speed. In the fifth week he produced a sample of 178 million per cc., and in recent weeks all samples have ranged from 100 to 200 million.