Dutasteride is marketed pharmaceutically as Avodart, Avidart, Avolve, Duagen, Dutas, Dutagen, Duprost. For unknown reasons, early clinical trials for dutasteride were abruptly ceased in 2002 (1), then continued later.
Dutasteride is a 5-alpha-reductase inhibitor, meaning it blocks the action of the 5a-reducatse enzymes, that are responsible for 5a-reducing (converting) testosterone into dihydrotestosterone (DHT) by the addition of a double hydrogen bond.
Dutasteride inhibits both isoforms of 5a-reductase, therefore preventing the conversion of testosterone into dihydrotestosterone. This makes Dutasteride a reasonable treatment for Male Pattern Baldness (2). Of course, when you convert less Testosterone into Dihydrotestosterone, you increase testosterone levels by default (less conversion).
Dutasteride, at 2.5mgs/day is roughly 1.5x more effective than Finasteride at 5mgs/day, at treating hair loss (both halting it as well as regrowing it). In addition, Dutasteride can be used successfully at that same dose to treat prostate enlargement (3), and a lesser known effect of Dutasteride (again, at that same dose) use is to treat Acne (4) caused by an overabundance of androgens in the body.
For the steroid using athlete suffering from DHT-related side effects, Dutasteride may be the answer. Hairloss, Acne, and prostate growth can all (potentially) be completely halted with the use of this product. Unfortunately, DHT is not all bad, and you potentially lose some muscle hardness (an amorphous quality if ever there is one), and even some of the other qualities we like from our androgen use.
Also…since this only prevents the 5a-reduction of the androgens subject to that conversion into a dihydro form of them…it will likely do nothing to stop hairloss or other symptoms caused entirely by the use of the androgens in the DHT family.