Effect of some antihistaminic drugs on the oestrous cycyle of rats.

The effect of some antihistaminic drugs namely antazoline hydrochloride, diphenhy, dramine hydrochloride and mepyramine maleate has been investigated on the oestrous cycle in albino rats. On daily intraperitoneal administration, for 6 days, all the three drugs (10 mg/kg) significantly (P less than 0.001) prolonged the duration of oestrous cycle. The duration of subsequent cycle returned to near normal.