LONDON (REUTERS) - Europe's medicines regulator has added an extremely rare nerve-damaging disorder, Guillain-Barre syndrome (GBS), as a possible side-effect of AstraZeneca's Covid-19 vaccine, regular safety updates from the watchdog showed on Wednesday (Sept 8).
The European Medicines Agency said a causal relationship between GBS and the AstraZeneca shot, known as Vaxzevria, was a "at least a reasonable possibility" after 833 cases of GBS were reported out of 592 million doses of the vaccine given worldwide by July 31.
The EMA categorised the side-effect as "very rare", the lowest frequency of side-effect category it has, and has emphasised that the benefits of the shot outweigh the risks.
The US Food and Drug Administration has added a warning over Guillain-Barre syndrome as a possible side-effect of Johnson & Johnson's shot.
Both vaccines use viral vector technology, and have also been associated with rare blood clots.
The EMA also tagged some other less severe side-effects to vaccines from Johnson & Johnson, Moderna as well as AstraZeneca's shot.