New atrial fibrillation drug effective but expensive
Those of you who have atrial fibrillation ( a common irregularity of heart rhythm) and take warfarin (Coumadin) know the drill all too well: Every month, sometimes more often, you make the trip to the laboratory or doctor's office to have a needle stick or finger stick to determine whether you are taking the proper dose of medication. No one likes it, many complain, and I don't blame them. But because of the increased risk of stroke faced by most patients with atrial fibrillation, medications to help prevent stroke are critical. Until now we had no reasonable alternative to this effective anticoagulant, or "blood thinner."
But in the fall of 2010 the FDA approved an exciting new drug, dabigatran (marked under the brand name Pradaxa), which was available in pharmacies November 3. This drug has been shown in clinical study to be more effective than warfarin in preventing stroke and intracranial hemorrhage (bleeding into the brain) with an overall similar risk of other major bleeding complications. It is simple to take, just one capsule twice daily, and requires no routine laboratory monitoring. Side effects are similar to warfarin except for a slightly higher incidence of mild stomach upset.
Of course, this convenience comes at a significantly higher cost: approximately $200 per month vs. $15 per month for generic warfarin. Yikes! Hopefully the improved stroke rate and similar bleeding risk seen with dabigatran will encourage insurance companies to place this drug on their formularies.
If you and your doctor are considering switching to this medication, please keep a few other issues in mind:
*Lots of drugs interact with warfarin, creating the need for increased monitoring when some medications are added to your regimen or stopped. Dabigatran has very few drug interactions (basically just one, an antibiotic called rifampin). This is really cool, because drug interactions are a big deal.
*Warfarin has been around for decades, so despite its inconveniences most physicians and other providers know how to use it, how to handle bleeding complications, and how to safely interrupt therapy around the time of surgery or invasive procedures. There is even an "antidote" available if too much warfarin is taken. Dabigatran has no "antidote," and must be handled differently in the setting of surgery or procedures. However, the drug disappears from the body far faster than warfarin, so many times if non-life-threatening bleeding occurs all that needs to be done is temporarily stop the drug.
*Let's face it, everyone forgets to take a pill now and then. With warfarin this usually isn't a big deal since the drug has a very long duration of action (although I strongly recommend always taking warfarin as prescribed). But with a shorter-acting drug like dabigatrin, missing even just a dose or two can increase the risk of stroke.
*And for now warfarin will continue be the only approved therapy for other conditions that require anticoagulant therapy, such as artificial heart valves and blood clots in the legs or lungs. I think this drug is going to be a very big deal in the field of cardiology. Talk to your physician if you think you might be a candidate.
Dr. David Nichols has practiced Internal Medicine in Price since 1991 and serves as the Medical Director for the Intensive Care Unit at Castleview Hospital