March 1, 2024

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Pfizer COVID-19 vaccine allergic reaction may originate from polyethylene glycol

Pfizer COVID-19 vaccine allergic reaction may originate from polyethylene glycol



Pfizer COVID-19 vaccine allergic reaction may originate from polyethylene glycol. In the past two weeks, at least 8 people have developed severe allergic reactions after receiving Pfizer’s COVID-19 vaccine. The “Science” website pointed out that the allergen is likely to be polyethylene glycol used to encapsulate mRNA molecules in vaccines.

Reports indicate that polyethylene glycol has never been used to make vaccines, but this ingredient is present in some drugs that often cause allergies. A small number of people who have been exposed to polyethylene glycol have high levels of anti-polyethylene glycol antibodies.

Once exposed to the vaccine, allergic reactions may occur, such as skin rash, sudden drop in blood pressure, shortness of breath, and rapid heartbeat. Of the 272,000 people vaccinated in the United States, 6 cases of allergic reactions have occurred, and 2 cases in the United Kingdom.

At present, the National Institute of Allergy and Infectious Diseases (NIAID) has held several meetings to discuss allergic reactions with Pfizer and Moderna representatives, independent scientists, doctors, and the FDA. NIAID is also conducting research with the FDA to analyze some people with high levels of anti-polyethylene glycol antibodies and previous severe allergic reactions to drugs or vaccines.

Pfizer said that the company is actively seeking follow-up, suggesting that appropriate medical and management measures should be provided during the vaccination process, so that if allergies occur, they can be rescued as soon as possible.




Why does the COVID-19 vaccine need to use polyethylene glycol?

As a good thickener, softener and moisture carrier, polyethylene glycol is very common in daily products, such as toothpaste and shampoo. It can be used as a laxative ingredient. More and more drugs also contain polyethylene glycol. Diol. Both Pfizer and Moderna vaccines are mRNA vaccines, and their main components need to be encapsulated in lipid nanoparticles to enter human cells. The use of polyethylene glycol can make these nanoparticles more stable and have a longer lifespan.




Why does polyethylene glycol cause severe allergies?

For a long time, people thought that polyethylene glycol is biologically inert, but more and more evidences show that it has certain safety risks. A 2016 study by Professor Samuel Lai, a pharmaceutical engineer at the University of North Carolina at Chapel Hill, found that 72% of humans have anti-polyethylene glycol antibodies, which may be due to exposure to cosmetics or drugs, and about 7% of humans have antibody levels high enough to trigger Allergic reaction. Therefore, some companies have abandoned the use of polyethylene glycol in their products.

In 1999, Walter Reed Army Research Institute Szebeni discovered a non-specific immune response to nanoparticle drugs. Once polyethylene glycol is recognized in the body, it will be marked as a virus by the immune system to initiate an immune response, such as Anticancer liposomes of adriamycin hydrochloride.

In 2014, in a clinical study of 1,600 people at Duke University, 0.6% of people had a severe allergic reaction and 1 person died, leading to the suspension of the trial. These people with severe allergic reactions all contain antibodies against polyethylene glycol. However, some people with no adverse reactions also have high levels of antibodies, so there may be other causes of allergies.





Why haven’t I found allergic reactions before?

Tens of thousands of people participated in the vaccine clinical trials of Pfizer and Moderna, and there were no serious adverse events. However, both studies excluded people with a history of allergies to vaccine components, and Pfizer also specifically excluded people who had serious adverse reactions to any vaccine. They did not exclude people with food or drug allergies.

Pfizer COVID-19 vaccine allergic reaction may originate from polyethylene glycol




Some scientists believe that the allergen is not polyethylene glycol

Moein Moghimi, a nanomedicine researcher at Newcastle University, believes that this allergic reaction is likely to be a more traditional mechanism. Vaccine adjuvants can activate the local immune system response, so it happens that some people’s immune system is overexcited, and the high number of local cells may also cause severe allergies.

It has also been pointed out that the polyethylene glycol content in mRNA vaccines is several orders of magnitude lower than that of common drugs, and that this vaccine requires intramuscular injection, which has less content into the blood and is less likely to cause allergic reactions.

Katalin Karikó, Senior Vice President of BioNTech, the inventor of two vaccine gene technologies, said that given the low content and intramuscular injection, the risk of allergies is negligible. All vaccines have risks, but the benefits clearly outweigh the risks.

The topic of whether polyethylene glycol causes allergies has not yet been determined, but a problem that needs to be faced during the vaccination process is that this vaccine needs to be vaccinated twice. The first vaccination triggers the production of anti-polyethylene glycol antibodies in the body. Increase the risk of allergic reactions during the second injection.




Observe for 30 minutes after vaccination

The United States is studying the mechanism behind allergic reactions and how often they occur. Experts suggested that the biomarkers of allergic reactions can only stay in the blood for a few hours. Therefore, a detection mechanism needs to be established, and blood samples should be taken in time for testing from future allergy cases.

Even if polyethylene glycol is really the culprit, it is difficult for us to screen millions of people for antibodies. Therefore, the CDC recommends that anyone with a history of severe allergies to the vaccine should not be vaccinated; for people who have an allergic reaction to another vaccine or drug, the risks and benefits of vaccination should be weighed. People who may be at high risk of allergies should observe for 30 minutes after vaccination, and treat them in time if an accident occurs.

At least, allergic reactions occur quickly, so we can be vigilant as early as possible, and do early identification and treatment.


(source:soshu, reference only)


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Important Note: The information provided is for informational purposes only and should not be considered as medical advice.