ROANOKE TIMES
Copyright (c) 1997, Roanoke Times
DATE: Saturday, February 8, 1997 TAG: 9702100043
SECTION: VIRGINIA PAGE: A-1 EDITION: METRO
SOURCE: SANDRA BROWN KELLY STAFF WRITER
FOR PEOPLE, the compound helps hearts; for rodents, it's a trip to that big cheese in the sky.
The story of warfarin, the effective ingredient in the blood thinner Coumadin, began in a pasture, according to Roanoke pharmacist Tom Harvey. Harvey wrote a paper about how the drug was discovered, part of his college studies in the 1950s.
Cattle began dying in the pasture; researchers looking for the cause discovered that a type of clover the livestock ate caused their blood to thin, making them bleed easily. The roughage in their stomachs worked against the blood vessels to cause the bovines to bleed to death internally.
From those findings, researchers created a lifesaver for humans, Coumadin, and a death warrant for rats, DeCon Rat Killer, which is warfarin mixed with ground glass, Harvey said.
Coumadin - generic name warfin sodium - is used to prevent or treat a blood clot, which could reach the heart or lungs and cause a heart attack or stroke.
It's a powerful substance that is unforgiving if too much is taken and doesn't work as well if too little is included. Generics, which are less expensive than name brands, can contain slightly less or slightly more of the drug, the amount depending on guidelines from the Food and Drug Administration.
That's why some pharmacies do not substitute a generic version for Coumadin.
Other drugs defined as "narrow therapeutic index drugs" and included in a Voluntary Formulary of those drugs are carbamazephine (used for epilepsy), estrogens (replacement therapy), digoxin (heart stimulant), levothyroxine (thyroid deficiency), phenytoin (convulsion blocker) and theophylline sustained release (muscle relaxant).
Substitution of the generic form of these drugs would be forbidden under legislation proposed in Virginia.
Warfarin, named for the Wisconsin Alumni Research Foundation, can interact with a variety of substances, especially alcohol, aspirin and ibuprofen, and even with large amounts of foods rich in vitamin K, which include asparagus, fish, cauliflower and beef liver, according to prescription drug guides.
People who take the drug should carry a card saying so.
LENGTH: Short : 50 lines KEYWORDS: GENERAL ASSEMBLY 1997by CNB