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Seizures in vaccine leaflet relate to rare blood clots in brain

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Nicola Swanborough

Seizures in vaccine leaflet relate to rare blood clots in brain

Callers to our Helpline have expressed concerns that the latest version of the patient information leaflet for the Covid-19 Astra Zeneca vaccine, mentions seizures as a possible side effect.

These seizures, however, are ‘symptom seizures’ which relate specifically to the rare cases of a blood clot as a side effect of the vaccine. Where a blood clot affects the brain, it may cause seizures. 

Professor Ley Sander, Medical Director at the Epilepsy Society, said: “There have been some extremely rare cases of blood clots occurring after the Astra Zeneca vaccine in people who have low numbers of blood platelets. If someone has a blood clot in the brain, they may experience a seizure as a result.

“This does not mean that the vaccine is likely to exacerbate seizures in people with epilepsy. This warning relates specifically to symptomatic seizures as a result of a blood clot.”

If you have any concerns about side effects following any of the Covid-19 vaccines, always seek medical advice.


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