The Medical Letter on Drugs and Therapeutics
FROM
ISSUE
1286
Pharmacogenetic-Based Dosing of Warfarin
The full article is available to subscribers Subscriber Login   
Revised 6/9/08: Table 1: Acetaminophen (Tylenol*) was added.

Warfarin sodium (Coumadin, and others) and other coumarin anticoagulants prevent thrombosis, but patient response is highly variable and overanticoagulation can lead to hemorrhage.1 Genotyping patients for single nucleotide polymorphisms (SNPs) that affect coumarin metabolism and sensitivity may help clinicians estimate the therapeutic warfarin dose. The FDA has added a note to warfarin labeling recommending lowrange doses for patients with such genetic variations. Commercial tests for these variants are now available and cost about $500 per test.

CLINICAL DOSING — Traditionally, warfarin has been dosed empirically, with the initial dose based on the indication and perhaps the weight and age of the patient. By adjusting the dose based on the International Normalized Ratio (INR) response, clinicians eventually arrive at the therapeutic dose. ... more      

The Medical Letter is a subscriber-funded nonprofit organization that publishes critical appraisals of new prescription drugs and comparative reviews of drugs for common diseases.

Would you like to read the rest of this article?  Gain access below.

Subscribe
Subscriptions to The Medical Letter on Drugs and Therapeutics include:
  • Print version published and mailed biweekly (26 issues/year)
  • Immediate Online access to current issue and archives from 1988 to the present
  • Mobile access to our mobile site and free apps for iOS, Android and Kindle
  • FREE online per issue CME/CE
Free trial offer
3 Free Issues of The Medical Letter on Drugs and Therapeutics mailed to your home or office PLUS online access.
Try a Free Trial Subscription
Purchase this article:
Title: Pharmacogenetic-Based Dosing of Warfarin
Article code: 1286b
 Electronic, downloadable article - $25