Blood clots are an extremely rare but serious side effect of the AstraZeneca COVID-19 vaccine, regulators said on Wednesday.
The benefits of the AstraZeneca vaccine continue to outweigh the risks, the European Medicines Agency (EMA) said in a press release. However, 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 answer to stop the bleeding in case of injury, but these blockages can cause problems if they interrupt the blood flow in 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 appeared in the veins of the human brain.
These clots, known as cerebral venous sinus thrombosis (CVST), can lead to stroke, seizures and death.
To date, most reported clots have occurred in women under 60 within 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 not receive the AstraZeneca vaccine unless they have already received the first dose.
Symptoms of a blood clot include shortness of breath and headache
The EMA said that patients who received the AstraZeneca vaccine should seek medical attention immediately if they experience the following symptoms:
- difficulty breathing
- chest pain
- swelling of the foot
- persistent abdominal (abdominal) pain
- 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 vaccination.
But if you have severe or persistent symptoms about four to 20 days after vaccination, you should seek medical attention, according to the World Health Organization.
Blood clots are usually treated with anticoagulants. Complications can be avoided if the clot is caught early.
This article was originally published by Business Insider.
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