AstraZeneca COVID-19 vaccine to get a blood clot warning in Canada

Health Canada indicated Tuesday, March 23, that it has started the process of adding a new blood clot warning to the Oxford-AstraZeneca COVID-19 vaccine. Officials confirmed, however, that they still believe the vaccine is safe and effective.  

The warning, once implemented, would inform patients that they should seek medical assistance if they notice any symptoms of a potential blood clot. Symptoms listed specifically by Health Canada included a sudden headache, a headache that persists for three days, shortness of breath and tenderness in the calves or legs.

“Overall, we are not making any changes to the recommendations at this time,” Supriya Sharma, MD, Health Canada’s chief medical advisor, explained in a video. “The issue of looking at this specific type of clot is ongoing, as it is for all blood clots in general. And … the information that we’ve seen in terms of more common types of clots, in general, has not shown any increased risk with people getting the AstraZeneca vaccine compared to people not getting the vaccine.”  

The AstraZeneca vaccine has been the focus of many recent controversies. While numerous countries temporarily paused the use of the vaccine over blood clot concerns, the World Health Organization and European Medicines Agency have both repeatedly indicated that this does not appear to be a significant issue.

Also, in the United States, federal health officials have said that AstraZeneca may have provided outdated information when commenting on the effectiveness of its vaccine. AstraZeneca answered that it would provide updated information within 48 hours.

Michael Walter
Michael Walter, Managing Editor

Michael has more than 18 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.

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