Definitions for "Premarin"
A hormone replacement therapy drug made from pregnant mares' urine (PMU), collected from horses who are confined in stalls for half the year, strapped to urine collection funnels. Click to learn more.
Brand name of the first commercially available conjugated estrogens.
Conjugated estrogens. An estrogen supplement created primarily from the urine of pregnant mares; while the ingredients are natural to horses, they are not natural to humans, and so therefore Premarin is essentially a synthetic estrogen.