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Important Update SymbolQuestion: Does the Janssen (Johnson & Johnson) vaccine contain PEG?

Answer: No. The Janssen COVID-19 vaccine includes the following ingredients: recombinant, replication-incompetent adenovirus type 26 expressing the SARS-CoV-2 spike protein, citric acid monohydrate, trisodium citrate dihydrate, ethanol, 2-hydroxypropyl-β-cyclodextrin (HBCD), polysorbate-80, sodium chloride. You can view the vaccine fact sheet here. (

Question: I reviewed the FAQ section on the AAAAI COVID-19 resources for clinicians, and I did find your advice on the use of daily oral steroids and interaction with the COVID-19 vaccine. I have a 68 yo male patient who has received 80mg of kenalog intra-articularly recently, and will be 11 days out of the intra-articular injection by the time he receives his first COVID-19 vaccine. For patients receiving long-acting steroid regimens, would you recommend a 4 week vs 2 week waiting period prior to the vaccine, if possible?

Answer: It depends on whether this was a depot steroid injection or an immediate acting injection.  If immediate acting, I think that two weeks is reasonable.  Immune suppression with corticosteroids usually requires several weeks of therapy, although depot injections can sustain the steroid dose for up to 6 weeks.  In that case, receiving the vaccine as soon as possible is preferred, before the immunosuppression begins.

Question: What recommendations can be given to patients who have been vaccinated regarding what they should do if exposed to a person with COVID-19?

Answer: Vaccinated persons with an exposure to someone with suspected or confirmed COVID-19 are not required to quarantine if they meet all of the following criteria: 

  • are fully vaccinated (two weeks or more after the final vaccine dose), 
  • are within 3 months following receipt of the final dose,
  • and have remained asymptomatic since the current exposure. 

Question: Should a patient who takes Singulair and Symbicort discontinue these medications two weeks prior and two weeks after the COVID19 vaccine? If these medications modify the immune system should these medications be held? 

Answer: No, there is no impact on an individual’s ability to respond to the vaccine and control of asthma is essential! There is no data to suggest that inhaled corticosteroids and/or leukotriene receptor antagonists impact on immunogenicity of the mRNA COVID-19 vaccines.

Question: CDC recommendations say not to pre-treat with antihistamines so as to not “mask” a reaction. However, I think for those patients that have known allergies or a background of allergies, pre-treatment makes sense. We tell patients to pre-treat before immunotherapy, to pre-treat before Aspirin desensitization, and pre-treat in some cases before OIT. Antihistamine pretreatment can blunt the severity of a reaction and buy time in management, which might be an advantage in venues where the vaccine is being given by personnel who are not trained in allergy management. Why not pre-treat before the vaccine in patients that have a background of allergy? 

Answer: Antihistamines are not contraindicated and can be given before the vaccination, although this approach is not recommended as a routine. One can make arguments either way as to whether this would hide or prevent a more serious reaction. In cases where the vaccine is administered without immediate availability of medical expertise, I would be concerned that the staff might miss a serious reaction if initial symptoms are blunted by the administration of the antihistamine before the vaccination.

Question: I assume with high dose steroids (>20mg/day) for prolonged periods, that the COVID vaccine should be deferred until at least several weeks. Any guidance with low dose or IM steroids and timing of COVID-19 vaccine?

Answer: Daily oral steroids may interfere with the antibody response to the vaccine based on data with other immunosuppressives and flu vaccine. If the dose can be safely stopped, then waiting two weeks may be a reasonable approach. If the steroids cannot be stopped, we would not delay administration of the vaccine as the risks associated with COVID infection outweigh the potential impaired response.

Question: Should a patient delay allergen immunotherapy (AIT) because they are receiving one of the mRNA COVID 19 vaccines?

Answer: The COVID 19 Task Force does not anticipate any contraindication for patients on AIT. However, it would be best to not get the two shots within 48 hours of each other to avoid confusion should a reaction occur.

Question: Is there any cross-reactivity between gelatin and PEG? I have a patient who experienced anaphylaxis to gelatin in vaccine and foods. Is she likely to react to the COVID-19 vaccines? 

Answer: There is no gelatin in either the Pfizer or Moderna vaccine. To my knowledge there is no cross reactivity between PEG and gelatin. PEG is not found in other vaccines, except for Hepatitis A. If she had anaphylaxis to a vaccine other than the Pfizer or Moderna, then a 30-minute observation period is recommended. 

Question: We are a large Allergy and Asthma group and many patients, due to the new vaccine, are asking if we test for polyethylene glycol and polysorbate. Is there a protocol in place for this? Your information on this matter will be greatly appreciated.

Answer: Our Task Force would not recommend routine skin testing for PEG in patients prior to vaccination unless they have a history of a severe allergic reaction to an injectable medication, or a history of a possible reaction to PEG. Skin testing is not standardized and the predictive value of skin testing is not known. Skin testing to PEG has been associated with systemic reactions. Furthermore, it is still not known if an allergy to PEG is the reason for allergic reactions to the SARS-CoV-2 vaccine. Routine testing, given these unknowns, may exclude people from receiving the vaccine unnecessarily, but could also potentially clear a patient for the vaccine who could still have a reaction. We refer you to 2 articles from JACI-IP in the last 2 years that may offer more insight: Polyethylene Glycol: Not Just a Harmless Excipient (jaci-inpractic and Polyethylene Glycol-Induced Systemic Allergic Reactions (Anaphylaxis) (

Question: As a practicing Allergist/ Immunologist, I perform patch testing at my office for the evaluation of contact dermatitis/ urticaria. Over the years, I have noticed that several patients have positive patch tests to PEG, one of the components of the Pfizer and Moderna COVID-19 vaccines. Indeed, when eliminating products that contain PEG, the skin symptoms abate. What advice shall I give these patients in terms of whether to receive the now available vaccines, or not? Please note that some of these patients have severe contact allergies to PEG.

Answer: We would suggest that the patient be skin tested for an IgE-mediated reaction to PEG. Contact dermatitis secondary to PEG is not IgE-mediated, so we don’t know what the risk would be for vaccination. The patient should also be queried about systemic reactions to medications or products that contain PEG.

Question: How should we treat patients with mastocytosis and the COVID Vaccines?

Answer: We do not see a contraindication for COVID 19 vaccination for mastocytosis patients. These patients would likely be in to the 30 minute wait group as they may have had a history of anaphylaxis (to any cause) separate from an mRNA vaccine or excipient in the vaccine.

Question: I am giving COVID-19 Pfizer vaccines at our hospital. We have had two anaphylaxis to date. Because this will be their only injection of that dosage based upon CDC guidelines, and with paucity of data on benefits of IV or oral steroid in anaphylaxis immediate care: Should we be looking at recommendation to avoid steroids in treating these patients with anaphylaxis? Most respond readily to 1-2 doses of epinephrine thus far. Steroids may blunt any precious antibody response?

Answer: In general, steroids are not needed or indicated for treatment of anaphylaxis. Treatment should be injectable epinephrine. Indeed, the recent practice parameters indicate no proven utility for use of steroids in acute anaphylaxis (J Allergy Clin Immunol. 2020;145(4):1082-123). Therefore, in response to this question, the answer would be to not administer steroids, but to treat the anaphylaxis with injectable epinephrine.

Question: What advice should we give patients who are allergic to several medications about the COVID-19 vaccine?

Answer: At the date of this response (December 19, 2020), only the Pfizer-BioNTech COVID-19 is available for administration in the U.S.   This is a dynamic process, so stay current on any changes in recommendations.  A summary of current recommendations are as follows:

Patients with allergies to oral medications (including oral equivalent of injectable medications), foods, insect, latex and environmental allergens have no restrictions and are recommended to receive the vaccine, followed by a 15-minute observation period.

Patients with non-serious reactions to vaccines or other injectables also have no restrictions, and are recommended to receive the vaccine, followed by a 15-minute observation period.

Patients with a history of severe allergic reactions (eg anaphylaxis) to vaccines (other than Pfizer-BioNTech COVID-19) or history of severe allergic reaction to any injectable medication, should be assessed for risk.  The CDC ACIP suggests considering potential deferral of vaccination, and to observe for 30 minutes, if vaccination is given.

Patients with a history of severe allergic reactions (eg anaphylaxis) to any component of the Pfizer-BioNTech or Moderna vaccines should not receive the vaccine.

In all cases, equipment and medications should be available to treat any potential anaphylactic event.

Question: I’m trying to research if there’s any guidance on patients receiving immunotherapy for their allergies and getting the COVID vaccine. Specific question I have would be: Should allergy shots be held for any amount of time before or after the COVID vaccine?

Answer: We do not anticipate any contraindication for patients on AIT. However, it would be best to not get the 2 shots within 48 hours of each other to avoid confusion should a reaction occur.

Question: I have a patient that was diagnosed with COVID-19 one month ago. She has had long-standing, uncontrolled allergic rhinoconjunctivitis, and she would like to start allergen immunotherapy. Would there be any reason to suggest a certain waiting interval after her diagnosis before starting AIT?

Answer: Provided your patient had a mild, uncomplicated clinical course of COVID there is no reason to delay immunotherapy. On the other hand, if your patient had a more severe course or is immunocompromised, then viral shedding can continue for >28 days. Aydillo T, et al. (1) reported that some immunocompromised people may shed infectious novel coronavirus for at least two months after diagnosis, rather than the 10 days demonstrated in uncomplicated cases. The patients in the study had become immunocompromised after receiving stem cell transplantation, immunosuppressive therapy, or chemotherapy for various cancers. I feel that we can apply this rationale to other immunocompromised conditions.

1) Aydillo T, Gonzalez-Reiche AS, Aslam S, van de Guchte A, Khan Z, Obla A, Dutta J, van Bakel H, Aberg J, García-Sastre A, Shah G, Hohl T, Papanicolaou G, Perales MA, Sepkowitz K, Babady NE, Kamboj M. Shedding of Viable SARS-CoV-2 after Immunosuppressive Therapy for Cancer. N Engl J Med. 2020 Dec 1. doi: 10.1056/NEJMc2031670. Epub ahead of print. PMID: 33259154


Question: If a patient has had COVID19 infection and recovered, then do they even need the vaccine? Or should we check IgG to COVID19 virus first and if not in protective range then give the vaccine?

Answer: Yes. The COVID Vaccine is recommended in a patient that has a history of COVID. There is no need to check antibody. Recurrent infections have been reported. It is felt that the vaccine will provide superior protection.

Question: Post Covid we have been using albuterol inhaler for doing pre- and post-spirometry. There is discrepancy as how many puffs (2 or 4) of albuterol inhaler we use prior to post bronchodilation spirometry?

We have been using 4 puffs (1 puff each 1 minute apart) waiting 10 minutes before doing post bronchodilation spirometry. Wondering if this any data to validate that dosing and timing?

Answer: You are correct, although 30 seconds in between would be adequate, rather than 1 minute.

Sim YS, Lee JH, et al. (1) provide a very thorough review of pre- and post-bronchodilator spirometry. The recommended procedure for albuterol is as follows. In the albuterol (short-acting β2-bronchodilator) bronchodilator test, the subject fully exhales slowly, and sprays an albuterol metered dose of 100 µg (1 puff) while biting a valved chamber. The subject then slowly and deeply inhales until reaching TLC over 3–5 seconds, holds the breath for 5–10 seconds, and exhales. This procedure is repeated four times (total 400 µg of albuterol), at intervals of 30 seconds. After inhalation of the last medication, the spirometry test is conducted again between 10–20 minute (1)

Also relevant to your question is this technique appropriate in a post-COVID patient. Grandbastien M, Piotin A, et al. (2) published an exceptional paper in J Allergy Clinical Immunology Practice. They studied 106 patients with SARS-CoV-2 between March 4 and April 6, 2020, who were hospitalized in the Chest Diseases Department of Strasbourg University Hospital; 23 had asthma.

The authors did not observe any increase in severe exacerbation with the development of SARS-CoV-2 pneumonia. This result is not in line with other respiratory viruses, such as Rhinovirus. In contrast to other respiratory viruses, SARS-CoV-2 may not be a risk factor for severe asthma exacerbation.

They further report that several hypotheses can be raised. ACE2 has been shown to be the functional receptor of SARS-CoV-1. This receptor is abundantly expressed in type I and type II pneumocytes, whereas bronchial epithelial cells exhibit only weak staining.

This study suggests that the risk factors for hospitalization in asthmatic patients were related more to the risk factors of SARS-CoV-2 pneumonia than to asthma.

In summary, in contrast to other viral respiratory infections, SARS-CoV-2 pneumonia did not appear to induce severe asthma exacerbation.


1) Sim YS, Lee JH, Lee WY, et al. Spirometry and Bronchodilator Test. Tuberc Respir Dis (Seoul). 2017;80(2):105-112. doi:10.4046/trd.2017.80.2.105

2) Grandbastien M, Piotin A, Godet J, et al. SARS-CoV-2 Pneumonia in Hospitalized Asthmatic Patients Did Not Induce Severe Exacerbation. J Allergy Clin Immunol Pract. 2020;8(8):2600-2607. doi:10.1016/j.jaip.2020.06.032

Some answers have been updated to reflect changing circumstances and information since the individuals submitting the questions were originally provided with a response. While we’re working on keeping answers updated as best we can, information continues to evolve rapidly. Please email us at with concerns or additional questions.