Kinship Circle

The P In Premarin Stands For Pee
By Brenda Shoss, Kinship Circle
Thanks to my late father, a drug made from animal waste is the most widely prescribed drug in the world today. Premarin has a secret ingredient that my father had no trouble accepting:
animal suffering.
~  Ron Wilson, son of Dr. Robert A. Wilson, who dubbed menopause a "living decay."


PEE. YEP, PEE. To acquire Premarin's "complex blend of natural estrogens," over 80,000 pregnant mares stand on pee lines in the U.S. and Canada. But you won't find urine listed on the bottle of this 60-year-old hormone replacement therapy. In fact, no one seems able to classify the mystery stuff inside Premarin, PremPro, PremPhase and PremPac.

"Because it is animal based, we don't know exactly what's in it…and you can't tell the horses what to pee," asserts Dr. Alan Altman, Harvard Medical School's assistant clinical professor of obstetrics, gynecology and reproductive biology. Last August Premarin manufacturer Wyeth-Ayerst, a division of American Home Products, endured its third recall. The FDA questioned the consistency of estrogen extracted from horses going to potty (estradiol yield can fluctuate nearly 400 percent from batch to batch) and the drug's ability to dissolve uniformly.

So how much pee is too much pee? According to a 2002 FDA report, continuing use of Premarin or Prempro can boost risk for "coronary heart disease (CHD), invasive breast cancer, stroke pulmonary embolism (PE), endometrial cancer, colorectal cancer, hip fracture, or death due to other cause."

This data comes from the Women's Health Initiative, a National Institutes of Health (NIH) study to assess risks/benefits linked with long-term use of Prempro and Premarin. On July 9, 2002 NIH abruptly halted its investigation and the government issued a cautionary letter about the drugs' potential hazards. The news shocked some 9 million women on HRTs for menopause and osteoporosis.

"Thanks to my late father, a drug made from animal waste is the most widely prescribed drug in the world today," writes Ron Wilson, son of Dr. Robert A. Wilson, the HRT guru who dubbed menopause a "living decay." In pursuit of the timeless woman, Dr. Wilson touted estrogen drugs as vital for reproduction after middle age. "Unfortunately," the younger Wilson says, "Premarin has a secret ingredient that my father had no trouble accepting: animal suffering."

Premarin comes from pregnant mares immobilized in cramped stalls.
At PMU (Pregnant Mare Urine) farms, mares are re-impregnated within days of birth so their bodies continually produce estrogen in the last six months of each cycle. Mares are harnessed in fixed positions with limited exercise. Unable to shift direction or recline with ease, many suffer bloated, painful legs and exhaustion.

Rubber urine-collection bags strapped over their urethras lead to leg chafing and infected sores. To harvest urine with a high consolidation of estrogens, farmers withhold drinking water. Renal and liver disorders are widespread among PMU mares.

Foals are snatched moments after birth to replace spent mares on the pee line or go to the slaughterhouse. Roughly 70,000 PMU castoffs wind up at auctions where most are sold to feedlots to fatten them for the overseas horsemeat trade. In Europe and Asia, prime equine cuts go for $25 a pound.

Pre-weaned foals are trucked from auction to slaughterhouse in double-decker livestock trailers overpacked with a perilous mix of stallions, geldings, mares, miniature horses, thoroughbreds, draft horses, ponies, donkeys, and mules. When fighting erupts, "the killer-buyer may wrap the horse's muzzle with duct tape or bailing wire," writes Cheryl Kucsera in Premarin and Horse Slaughter: The Hidden Story. "Often, unruly horses are deliberately blinded by gouging out their eyes or shooting them in the eyes with a BB gun." During grueling treks, horses travel without food, water, or refuge from weather extremes.

Their last stop is the slaughterhouse.
Ambulatory animals dismount first. The dead and dying are hauled from the trailer in chains. The killing room reeks of death with, dazed and moaning horses in full view for newcomers. A frantic PMU mare is prodded from her narrow chute through the knock box door. Staggering over blood, urine and manure, she struggles to balance as workers fire a metal shunt into her brain. She may need two or three shots from the captive bolt gun before she passes out.

Next, she is cast onto a conveyor belt, bound by a hind leg, and suspended upside down in the air. She remains alive, sometimes regaining consciousness, as her throat is slit. To render meat suitable for human ingestion, the horse's pulsating heart must pump blood from her body.

For every 150 women who replace Premarin products with plant-based estrogen, one less mare endures the pee line — and seven or eight foals aren't someone's dinner.


  1. Do not take: Premarin, Prempro, Premphase, Prempac, Premelle, Aprela. Use cruelty-free natural options. Inform your doctor and other women.

  2. Urge your doctor to prescribe plant-derived HRTs. For information, literature, discussion boards, and ways to help, visit:

  3. Boycott goods from Wyeth-Ayerst/American Home Products. For a products list, see

    Let Wyeth know why you won’t use their products:
    Robert Essner, President and CEO, Wyeth-Ayerst
    5 Giralda Farms
    Madison, NJ07940
    ph: 800-999-9384

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