People with a “significant history” of allergic reactions should not have the Pfizer/BioNTech vaccine.
The warning comes after two NHS workers inoculated on Tuesday reported an allergic reaction.
Both are “recovering well”, NHS England officials said.
The Medicines and Healthcare products Regulatory Agency (MHRA) has now given precautionary advice to NHS trusts about the Covid-19 jab.
Professor Stephen Powis, national medical director for the NHS in England, said:
“As is common with new vaccines the MHRA have advised on a precautionary basis that people with a significant history of allergic reactions do not receive this vaccination after two people with a history of significant allergic reactions responded adversely yesterday.
“Both are recovering well.”