treatment of pattern hair loss in 1997. Epristeride was the second 5-ARI to be introduced and was marketed for the treatment of BPH in China in 2000. Dutasteride was approved for the treatment of BPH in 2001 and was subsequently approved for pattern hair loss in South Korea in 2009 and in Japan in 2015. The patent protection on finasteride and dutasteride has expired and both drugs are available as generic medications. Research 5-ARIs have been studied in combination with the nonsteroidal antiandrogen bicalutamide for the treatment of prostate cancer. See also List of 5α-reductase inhibitors Discovery and development of 5α-reductase inhibitors CYP17A1 inhibitor Neurosteroidogenesis inhibitor References Hair loss medications Hair removal Antiandrogens