Dear rb9909, Thank you for your clinical post. Male pattern hair loss can be a stressful and disheartening process for any young male. To reduce and retire the speed of thinning and recession Finasteride, also known as Propecia, is one of the gold standards. It blocks the production of testosterone at source in the testicle reducing the amount of DHT that builds up from the genetically determined inadequate functioning of the enzymes 5-alpha reductase. Other options other than hormonal blockade include topical vasodilatory products such as Rogaine or Minoxidil, plasma rich protein injections, topical nutrient serums and shampoos, as well as low-level light therapy. These have also shown to be successful though not as predictable or consistent in retarding the progression of hair loss as Finasteride. Unfortunately, some males do experience side effects with the use of Finasteride. These side effects include 1) a potential decrease libido; 2) a sexual dysfunction with erectile dysfunction with or without loss of libido; 3) mood changes, dysphoria and even depression; 4) sensation of urinary retention and 5) male gynecomastia. Muscle aches and bone pain can also occur. These symptoms are not necessarily common, but certainly warrant full discussion with a physician prior to having Finasteride prescribed and you should be wary and watchful for the appearance of any of these signs or symptoms. There is one study that suggests a very small group of males may be more predisposed to aggressive version of prostate cancer. However, this study is certainly controversial, but it bears consideration. I hope this information has been of some assistance. For more information, please review the link below. R. Stephen Mulholland, M.D. Certified Plastic Surgeon Yorkville, Toronto