SR9009

Finasteride is a selective type II 5-alpha reductase inhibitor approved for male pattern hair loss (1 mg, Propecia) and benign prostatic hyperplasia (5 mg, Proscar). It reduces scalp DHT levels by approximately 60-70% and is one of only two FDA-approved oral medications for androgenetic alopecia. It has decades of clinical data supporting its efficacy.

Tamoxifen is a selective estrogen receptor modulator (SERM) that has been the gold standard for breast cancer treatment and prevention since the 1970s. It is one of the most widely used compounds in post-cycle therapy (PCT) for restoring endogenous testosterone production after anabolic steroid use.

Clomiphene citrate is a SERM originally developed for female ovulation induction and widely adopted in PCT protocols and off-label male hypogonadism treatment. It is a racemic mixture of two geometric isomers, enclomiphene (trans) and zuclomiphene (cis), with differing estrogenic properties.

Anastrozole is a potent, selective non-steroidal aromatase inhibitor that reduces estradiol levels by approximately 80-85%. It is widely used in breast cancer treatment and is the most commonly employed AI during anabolic steroid cycles to manage estrogen-related side effects.