5-alpha-reductase inhibitors

taken from Small Gland, Big Problem 4th Edition
by Professor Roger Kirby, Health Press 2011

5-alpha-reductase inhibitors are used in BPH to block the conversion of testosterone to another substance, DHT, which appears to stimulate overgrowth of prostate tissue. Possible side effects include loss of libido, reduced erections and rarely minor breast enlargement.