Pfizer is warning Britain’s National Health Service not to give the company’s coronavirus vaccine to people with a significant history of allergic reactions. The drugmaker issued that guidance today after two NHS workers had what health officials called adverse responses. A patient information leaflet from Pfizer says signs of allergic reaction might include an itchy skin rash, shortness of breath, and swelling of the face or tongue…and bell’s palsy.

UK regulator dismisses Bell’s palsy fears over Pfizer’s Covid vaccine https://t.co/yt3sbiTNC3 via @MailOnline none on the placebo experienced it

— Independent Nation Of Kent (@chelseadagger41) December 9, 2020

As the United Kingdom began administering people with the Pfizer-BioNTech vaccine, four people who got Pfizer’s coronavirus vaccine in the firm’s trial developed Bell’s palsy, a form of temporary facial paralysis.

The FDA can’t confirm that the vaccine caused Bell’s palsy, but warned that doctors should watch for the alarming side effect.

Bell’s palsy is a condition that causes temporary weakness or paralysis of the facial muscles. It can usually occur when a nerve that controls the muscles becomes inflamed, swollen or compressed.

Meanwhile, Pfizer chief executive Albert Bourla said the company did not “cut any corners” while rolling out the vaccines.