The Pfizer mRNA vaccine and allergy
The Pfizer/BioNTech vaccination contains a type of Polyethylene Glycol (PEG) which can cause allergic reactions. PEGs are very widely used in several medicines such as laxatives and cosmetics such as toothpastes and skin creams; and most of the population will have been exposed to it before.
In the large Pfizer/BioNTech vaccine trial with over 43,000 participants, no serious safety concerns were observed. However, if you believe you may be allergic to PEGs, you should not take the vaccine until you have had a chance to discuss this with an allergy specialist.
Health officials currently recommend that people who have had an anaphylactic reaction to a food, medicine or vaccine should not be given the Pfizer mRNA vaccine without prior discussion with their doctors; and the vaccine shots should only be administered at sites equipped to deal with anaphylaxis.