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Alan Khadavi, MD, APC
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December 25, 2020 by Alan Khadavi

Moderna Covid Vaccine and Allergy

Currently there is 1 report of the Moderna Covid vaccine and allergy reactions. Earlier we wrote regarding the Pfizer Covid vaccine and allergic reactions.  So far in regards to the Pfizer vaccine a total of 6 cases in the U.S. have been reported and 2 in the U.K. The current statistics through December 19th, were 6 reactions out of 272,000 injections. The data may lag behind from what is reported.

As we noted on a previous post, Pfizer Covid Vaccine and Allergy, the scientists are honing on the chemical PEG, polyethylene glycol.  PEG is part of the fatty envelope that surrounds the messenger RNA, the main ingredient in the vaccine. Once the mRNA gets into cells, it teaches them to make a protein that resembles the spike protein found on the surface of the coronavirus. That induces a specific immune response that shores up the body’s defenses for when it is exposed to the real virus. The PEG-containing fatty envelope helps ensure the mRNA gets across the cell membrane and into the cells.

PEG is in both the Pfizer-BioNTech and the  Moderna vaccine, so it is possible that it may be PEG, although it’s still possibly something else.  The ingredients found in the Moderna vaccine are:

The Moderna COVID-19 Vaccine contains the following ingredients: messenger ribonucleic acid (mRNA), lipids (SM-102, polyethylene glycol [PEG] 2000 dimyristoyl glycerol [DMG], cholesterol, and 1,2-distearoyl-sn-glycero-3-phosphocholine [DSPC]), tromethamine, tromethamine hydrochloride, acetic acid, sodium acetate, and sucrose.

Side effects that have been reported with the Moderna COVID-19 Vaccine include:

• Injection site reactions: pain, tenderness and swelling of the lymph nodes in the same arm of the injection, swelling (hardness), and redness

• General side effects: fatigue, headache, muscle pain, joint pain, chills, nausea and vomiting, and fever.

There is a remote chance that the Moderna COVID-19 Vaccine could cause a severe allergic reaction. A severe allergic reaction would usually occur within a few minutes to one hour after getting a dose of the Moderna COVID-19 Vaccine. For this reason, your vaccination provider may ask you to stay at the place where you received your vaccine for monitoring after vaccination. Signs of a severe allergic reaction can include:

• Difficulty breathing

• Swelling of your face and throat

• A fast heartbeat

• A bad rash all over your body

• Dizziness and weakness

The CDC, FDA and allergy societies are closely monitoring for allergic reactions.

The vaccine is not contraindicated if you have a food, latex, environmental or venom allergy. The vaccine should only be administered in a place where allergic reactions can be treated (i.e. epinephrine should be available). Observation between 15-30 minutes is also recommended.

The NIH is devising a study on rare allergic reactions to the Covid vaccine, please check back up later for more updates if we see a link between the Moderna Covid vaccine and allergy.

The first allergic reaction from the Moderna Covid vaccine occurred on December 23rd, 2020 to Dr. Hossein Sadrzadeh, at Boston Medical Center. He described that after he was inoculated, he felt dizzy with his heart racing, his tongue prickled and went numb. He self administered an Epipen he was carrying for his shellfish allergy. He was taken to the ER and later discharged. He described it as “the same anaphylactic reaction that I experience with shellfish.” Data filings from Moderna did not report any links between its vaccine and anaphylaxis.

Filed Under: Anaphylaxis, Blog, Headlines

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Dr. Alan Khadavi
Allergy & Asthma Specialist

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