Blood clots are an extremely rare but serious side effect of AstraZeneca’s COVID-19 vaccine, regulators announced on Wednesday.
The benefits of the AstraZeneca vaccine still outweigh the risks, the European Medicines Agency (EMA) said in a press release. Still, the agency’s safety committee said it was 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 injury, but these blockages can cause problems if they cut 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 occurred in the veins of people’s brains.
These clots, known as cerebral venous sinus thrombosis (TSCV), can cause stroke, seizures and death.
So far, the majority of reported clots have occurred in women under 60 years of age in the two weeks of vaccination.
As young people are more likely to experience this side effect, UK vaccine regulators recommend that people under the age of 30 should not have an AstraZeneca injection unless they have already received their first dose.
Blood clot symptoms include shortness of breath and headaches
The EMA said that patients who received the AstraZeneca vaccine should seek medical attention immediately if they experience the following symptoms:
- shortness of breathe
- chest pain
- swelling in the leg
- 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 around four to 20 days after vaccination, you should seek medical attention, according to the World Health Organization.
Blood clots are usually treated with anticoagulant drugs. Complications can be avoided if the clot is detected early.
This article was originally published by Business Insider.
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