Advising individuals with allergies on their suitability for AstraZeneca COVID-19 Vaccine

Eimear Maguire, Senior Medicines Information Pharmacist, North West Medicines Information CentrePublished Last updated See all updates

Advice on whether people with a previous allergic reaction can have the AstraZeneca COVID-19 vaccine.

Background

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that:

  • those with allergies, including anaphylaxis, to a food, insect sting or most medicines (where the trigger has been identified), can proceed with vaccination as normal according to local guidelines, as long as they are not known to be allergic to any component (excipient) of the vaccine;
  • anyone with a family history of allergies, a previous non-systemic reaction to a vaccine, hypersensitivity to non-steroidal anti-inflammatory drugs (e.g. aspirin, ibuprofen) or mastocytosis can proceed with vaccination as normal, according to local guidelines.

Below is a summary of knowledge about suitability for vaccination based on previous allergy status.

First dose of AstraZeneca COVID-19 vaccine or other medicines allergy

Allergy to a previous dose of AstraZeneca COVID-19 vaccine or other medicines may affect suitability for vaccination. Public Health England’s Immunisation Against Infectious Disease (the Green book) states that:

  • Individuals with a prior history of systemic allergic reaction (including immediate-onset anaphylaxis) to a previous dose or any component of the AstraZeneca vaccine should not receive it.

Individuals with a history of immediate onset-anaphylaxis to multiple classes of drugs or an unexplained anaphylaxis should not be vaccinated with the Pfizer-BioNTech COVID-19 vaccine, except on the advice of an allergy specialist. However, the AstraZeneca COVID-19 vaccine can be used as an alternative (if not otherwise contraindicated), particularly if they previously tolerated an injected influenza vaccine. The vaccine should be administered in a setting with full resuscitation facilities (e.g. a hospital), and a 30 minute observation period is recommended.

See the main page in this series for advice on prior allergy to the 1st dose spanning all COVID-19 vaccines.

Excipients

The Information for Healthcare Professionals states that a hypersensitivity to any of the excipients is a contraindication to the vaccine use.

Excipients present

The excipients listed in the manufacturer’s information are as follows:

  • L-Histidine
  • L-Histidine hydrochloride monohydrate
  • Magnesium chloride hexahydrate
  • Polysorbate 80
  • Ethanol
  • Sucrose
  • Sodium chloride
  • Disodium edetate dihydrate
  • Water for injections

Polysorbate 80 allergy

The AstraZeneca COVID-19 vaccine contains polysorbate 80, according to the Information for Healthcare Professionals. Individuals with an allergy to polysorbate 80 should not receive the vaccine.

Polyethylene glycol (PEG) allergy

PEG is not present in the AstraZeneca COVID-19 vaccine, according to the Information for Healthcare Professionals; however, it does contain polysorbate 80.

Public Health England’s Immunisation Against Infectious Disease (the Green Book) advises that the AstraZeneca vaccine may be used as an alternative in people with a PEG allergy. The AstraZeneca COVID-19 vaccine contains polysorbate 80, according to the Information for Healthcare Professionals. The BSACI advise in their COVID-19 Vaccinations and Allergies FAQ that polysorbate 80 is found in many vaccines including the influenza vaccine; they state that although polysorbate 80 is quite similar in structure to PEG, there are no reports of PEG-allergic patients reacting to it e.g. when receiving other vaccines and therefore the AstraZeneca COVID-19 vaccine is recommended as a suitable alternative.

Public Health England’s Immunisation Against Infectious Disease (the Green Book) also states that it is unclear whether PEG is the only cause of allergic reactions in patients with systemic allergic symptoms after the first dose of the Pfizer-BioNTech vaccine. Patients with systemic allergic symptoms after the first dose of the Pfizer-BioNTech vaccine may be considered for a second dose using the AstraZeneca vaccine, and should be observed for 30 minutes following vaccination.

Other allergy considerations

As well as allergy considerations associated with previous vaccination and to excipients, other considerations are as follows.

Antibiotics

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that individuals with previous allergy to an identified drug, including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine.

Foods

Previous allergy to foods is covered in Public Health England’s Immunisation Against Infectious Disease (the Green book) which states that individuals with previous allergy to food, including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine.

Egg content

The manufacturer states that the vaccine does not contain eggs. However, AstraZeneca does not manufacture the raw materials used in its products, and the suppliers may periodically change. Lack of contact with other ingredients during the manufacturing process cannot be guaranteed.

Gelatin content

The manufacturer states that the vaccine does not contain gelatin. However, AstraZeneca does not manufacture the raw materials used in its products, and the suppliers may periodically change. Lack of contact with other ingredients during the manufacturing process cannot be guaranteed.

Gluten content

The manufacturer states that the vaccine does not contain any gluten. However, AstraZeneca does not manufacture the raw materials used in its products, and the suppliers may periodically change. Lack of contact with other ingredients during the manufacturing process cannot be guaranteed.

Nut content

The manufacturer states that the vaccine does not contain any peanut or tree nut derivatives. However, AstraZeneca does not manufacture the raw materials used in its products, and the suppliers may periodically change. Lack of contact with other ingredients during the manufacturing process cannot be guaranteed.

Soy content

The manufacturer states that the vaccine does not contain any soy. However, AstraZeneca does not manufacture the raw materials used in its products, and the suppliers may periodically change. Lack of contact with other ingredients during the manufacturing process cannot be guaranteed.

Latex

Our view is that the risks associated with previous latex allergy are low. The vaccine can be considered not to contain latex and poses the same minimal risk as other injectable medicines presented in vials with a halobutyl rubber stopper.

This view is formed from:

However, even if the components of an injection do not contain latex, or latex is not used as a raw material during manufacturing, most manufacturers of injectable products advise they cannot guarantee minute amounts of latex are not contained in raw materials obtained from their suppliers or the product has not come into contact with latex during the manufacturing process.

Patients with an allergy to latex can be directed to the Anaphylaxis Campaign website for information.

Other drugs

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that individuals with previous allergy to an identified drug, including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine. However, it also states that the following individuals should be discussed with an allergy specialist, prior to vaccination:

  • Those with a history of immediate onset-anaphylaxis to multiple classes of drugs with the trigger unidentified (this may indicate PEG allergy).
  • Those with a history of anaphylaxis to a vaccine, an injected antibody preparation or a medicine likely to contain PEG (e.g. depot steroid injection, laxative)

“Sulfa” medicines

Public Health England’s Immunisation Against Infectious Disease (the Green book) states that individuals with previous allergy to in an identified drug, including anaphylaxis, can receive the AstraZeneca COVID-19 vaccine.

The Information for Healthcare Professionals does not indicate that any “sulfa” medicines are present in the AstraZeneca COVID 19 vaccine.

Thiomersal content

The Public Health England’s Immunisation Against Infectious Disease (the Green book) highlights that thiomersal is a mercury based compound used as a preservative in the manufacture of some vaccines for many years and has been associated with some safety concerns.

The manufacturer states that this vaccine does not contain any preservatives, thiomersal or any mercury derived product.

Summary of allergy considerations

The table below is a pictorial summary of the management of patients with a history of allergy, reproduced with kind permission from authors of Public Health England’s Immunisation Against Infectious Disease (the Green book).

Also of interest

Managing anaphylaxis in the COVID-19 vaccination setting

29 December 2020Advice on managing anaphylaxis in the vaccination setting with specific reference to COVID-19 vaccines.

Change history

  1. Information on prior allergy common to all vaccines moved the main page covering common allergy points.

  2. Added "Flowchart for managing patients who have allergic reactions to the first dose of COVID-19 vaccine" to "First dose of AstraZeneca COVID-19 vaccine or other medicines allergy" section; added a new section "Summary of allergy considerations", including a summary table.

  3. Updated to reflect changes in the Green Book: "Background" section updated; "First dose of AstraZeneca COVID-19 vaccine or other medicines allergy" section updated, including addition of BSACI management advice for people who had a reaction to the first dose of vaccine; added which patients should be discussed with an allergy specialist prior to vaccination in the "other drugs" section.

  4. Changes made to include page as part of a series covering similar topics

  5. Changes made to clarify advice in relation to other allergy considerations, including addition of advice regarding latex

  6. Changes made to clarify advice in relation to allergies and excipients

  7. Polysorbate 80 information added.

  8. PEG section modified, based on updated information from the Green Book.

  9. Published