Leuprolide

How it works

A depot copy of GnRH, the brain's sex-hormone signal: testosterone surges in week one, then the pituitary shuts it off for months.

What it's made of

9 amino acids: GnRH with a D-leucine at position 6 and the final glycine replaced by an ethylamide. It resists enzymes and activates the receptor much more than the hormone does.

What it's for

Prescribed for

Advanced prostate cancer, endometriosis, fibroids with anemia, and central precocious puberty.