Endocrine Abstracts

Cimetidine, an H2 receptor antagonist, has been shown to be clinically valuable in the treatment of peptic ulcers. Recently, the effect of cimetidine on the reproductive system has been studied in detail and there are some reports showing the untoward effects of cimetidine on this system. In this paper was undertaken to evaluate the effect of cimetidine on serum testosterone, testes, prostate, seminal vesicle and vas deferens. Apart from the above objective,the mechanism through which cimetidine can affect sperm motility and count was also sought. Oral repeated dose studies in rats at dosage levels of 150, 378 and 950 mg/kg cimetidine for periods up to 12 months have been reported. Few adverse effects were noted at all dose levels and no significant differences between the groups were observed in body weight, food consumption, blood chemistry, urinalysis. The livers of the 950 mg/kg dose group were heavier than those of controls. This was attributed to increased metabolic work load. After 12 months dosing there was a reduction in the size of prostates of the rats in all dosed groups and a reduction in the size of testes and seminal vesicles of the top dose group. No histopathological abnormalities were attributable to cimetidine treatment.