Yaz, Yasmin Blood Clot Fears Spark Canadian Safety ReviewJun 8, 2011 | Parker Waichman LLP
Two studies published this year in the British Medical Journal have prompted Canadian regulators to launch a safety review of Yaz and Yasmin. The aim of the review is to determine if Bayer Corporation's popular birth control pills pose a higher risk of blood clots compared to pills made with a different type of progestin.
Yaz and Yasmin are made with a synthetic progestin called drospirenone. All birth control pills carry a risk of blood clots, but the two British Medical Journal studies reported that those made with drospirenone increased those risks significantly compared to pills made with levonorgestrel. They were just the latest of several studies that have reached conflicting conclusions about drospirenone and blood clots.
Yaz, Yasmin and other drospirenone-containing birth control pills have become popular because some women tolerate this type of progestin better, and some side effects, like water retention, are less severe compared to other pills. But drospirenone is known to carry other risks. For one thing, it can impact the body’s potassium levels, which can cause a condition known as hyperkalemia, and lead to serious health complications.
Health Canada said yesterday it will take appropriate action if necessary once the review is complete, including informing health professionals and Canadians of new safety information. The agency also reminded health care providers that birth control pills are not to be used in patients with an elevated risk for blood clots, including women over age 35 who smoke. Finally, Health Canada advised patients to seek medical attention immediately if they experience any signs of a blood clot, including leg swelling, leg pain or tenderness, chest (thoracic) pain, or sudden shortness of breath.
Yaz and Yasmin are the only drospirenone birth control pills sold in Canada. However, in the U.S., these types of pills are also sold under the brand names rand names Beyaz and Safyral. The hormone is also an ingredient in generic forms of Yaz (Gianvi, Loryna) and Yasmin (Ocella, Syeda, and Zarah).
In the U.S., the Food & Drug Administration (FDA) is also evaluating the safety of drospirenone contraceptives in light of the recent British Medical Journal studies. The findings also prompted European regulators to order label revisions for the drugs.