Blood clots are an extremely rare but serious side effect of AstraZeneca’s COVID-19 vaccine, regulators announced Wednesday.
The benefits of AstraZeneca vaccine still outweigh the risks, the European Medicines Agency (EMA) said in a press release. Still, the agency’s security committee said it’s important to know the signs of a possible clot.
A blood clot occurs when the blood thickens and forms a semi-solid mass. It can be a useful response to stop bleeding in the event of an injury, but these blockages can cause problems if they cut off blood flow to a vital area.
Blood clots can cause blockages in the legs, abdomen and lungs. Most of the blood clots associated with the AstraZeneca vaccine have occurred in people’s brain veins.
These clots, known as cerebral venous sinus thrombosis (CVST), can cause stroke, seizures, and death.
To date, most reported clots have occurred in women under 60 in the two weeks following vaccination.
As young people are more likely to experience this side effect, UK vaccine regulators recommend that people under the age of 30 not receive AstraZeneca unless they have already received the first dose.
Symptoms of a blood clot include shortness of breath and headaches
The EMA said patients who received the AstraZeneca vaccine should seek medical attention immediately if they experience the following symptoms:
- shortness of breath
- chest pain
- swelling in the bed
- persistent abdominal pain (belly)
- neurological symptoms, including severe and persistent headaches or blurred vision
Some mild side effects, such as pain at the injection site or other body aches, are common in the days after the vaccine.
But if you experience severe or persistent symptoms four to 20 days after vaccination, you should seek medical attention, according to the World Health Organization.
Blood clots are usually treated with anticoagulant medications. Complications can be avoided if the clot is caught early.
This article was originally published by Business Insider.
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