Dutasteride (also known as GI198745, GG-745; trade names: Avodart, Avidart) is a potent dual 5-α reductase inhibitor that inhibits conversion of testosterone to dihydrotestosterone (DHT).

Finasteride (also known as MK-906) is a potent, reversible, and orally bioactive inhibitor of the rat type II 5 alpha-reductase with Ki of 10.2 nM, used in the treatment of benign prostatic hyperplasia (BPH) and male pattern baldness (MPB).

Phenprocoumon (Marcumar), a coumarin derivative that acts as a long acting oral anticoagulant and an antagonist of vitamin K, is a vitamin K reductase with an IC50 of 1 μM. Phenprocoumon inhibits coagulation by blocking synthesis of coagulation factors II, VII, IX and X. It is used for the prophylaxis and treatment of thromboembolic disorders.