Premarin: the intriguing history of a controverisal drug

Premarin, a complex of conjugated equine estrogens manufactured by Wyeth for use as hormone replacement therapy in women, was originally developed by the Canadian pharmaceutical firm Ayerst, McKenna and Harrison. The name Premarin was coined from pregnant mare urine, from which the estrogen complex was isolated. Although the complete composition of Premarin and its active components remains undisclosed or unknown, Wyeth reports that it contains a mixture of 10 estrogens. The history of Premarin is entangled in a fascinating story of human intrigue involving ingenuity, influence, controversy, animal rights, competition, money, protection of stockholders, government regulatory power, patient rights, emotions, greed, power, personal and professional freedom, state rights, and perhaps even, ultimately, constitutional issues. As the saga of Premarin evolves, it no doubt will continue to be one of the more interesting and compelling stories of the practice of pharmacy.