Fertility studies on the effect on sperm cells in humans have not been carried out with Proviron. Use in pregnancy. Category X Proviron is for use in male patients only. Drug interactions which result in an increased clearance of sex hormones can lead to decreased therapeutic efficacy. This has been established with many hepatic enzyme inducing drugs including phenobarbital and phenytoin. Androgens have been reported to enhance the activity of a number of drugs, with Human Gonadotropin increases in toxicity. Drugs affected include cyclosporin, antidiabetics, thyroxine and anticoagulants, such as warfarin. Resistance to HCG for sale effects of neuromuscular blockers has also been reported. Effects on laboratory tests.