For example, the most commonly prescribed stroke preventative medication is aspirin. Aspirin works to prevent blood clots by preventing the clumping action of platelets, the blood’s clotting cells. Few people know that some patients cannot tolerate aspirin because long-term therapy can cause bleeding in the stomach.
Doctors also prescribe anticoagulants for stroke prevention. Anticoagulants are more commonly known as blood thinners, and they prevent strokes by inhibiting the body’s ability to form blood clots that can travel to the brain. Because these drugs stop blood clots, any minor injury such as a bump or a fall can cause uncontrollable bleeding that can lead to severe injury or death.
Newer is Not Always Better
Today, there are several new anticoagulants that have been recently released or are awaiting approval from the U.S. Food and Drug Administration or the European Medicines Agency (EMA). While these new drugs are more effective at preventing strokes, they may also trigger dangerous side effects in some people.
Boehringer Ingelheim released Pradaxa (dabigatran) in 2010, and the drug has been shown to be more effective at preventing strokes than warfarin–a blood thinner used since the 1950s. It is taken twice daily and requires no blood tests or dietary restrictions, which make it more convenient and easier to use. In the United States, Pradaxa is approved for preventing stroke in people with atrial fibrillation not caused by a heart valve problem. In Europe, it is also approved for preventing blood clots after knee and hip replacement surgery.
However, Pradaxa has also been linked to thousands of reports of uncontrollable bleeding and hundreds of deaths in the United States and Europe, causing many people to file lawsuits against Boehringer. In December 2012, both the FDA and EMA released urgent communications to doctors and patients warning them that Pradaxa should not be used in patients with mechanical heart valves because of a greater risk of stroke, heart attack and blood clots. Unlike warfarin, which has a vitamin K-based antidote, Pradaxa was released with no antidote. That means doctors cannot reverse the blood-thinning effect of the drug when a patient suffers a major bleed.
Another new anticoagulant called Xarelto (rivaroxaban) was approved in 2011, and Eliquis (apixaban) is scheduled to be approved soon. Both of these drugs also carry a risk of bleeding and because they are so new, little is known about who might be at risk. Newer drugs like Pradaxa and Xarelto are also more expensive than warfarin. People who have suffered a stroke should make sure they talk with their doctors about the benefits and risks of each medication before taking it.
Michelle Y. Llamas writes about dangerous drugs and medical devices for Drugwatch.com.
Sources:
World Heart Federation. (2012). Stroke. Retrieved from http://www.world-heart-federation.org/cardiovascular-health/stroke/
Span, P. (2011, October 5). New drugs to prevent strokes. New York Times. Retrieved from http://newoldage.blogs.nytimes.com/2011/10/05/new-drugs-to-prevent-strokes/
Institute for Safe Medication Practices. (2012, May 31). Anticoagulants the leading reported drug risk in 2011. Retrieved from http://www.ismp.org/quarterwatch/pdfs/2011Q4.pdf
Thomas, K. (2012, November 2). A promising drug with a flaw. The New York Times. Retrieved from http://www.nytimes.com/2012/11/03/business/a-rising-anti-stroke-drug-is-tied-to-risk-of-bleeding-deaths.html?_r=0
Husten, L. (2012, October 23). Setback for trial studying dabigatran after mechanical valve surgery. Forbes. Retrieved from http://www.forbes.com/sites/larryhusten/2012/10/23/setback-for-trial-studying-dabigatran-after-mechanical-valve-surgery/