Laxative Allergy: PEG Anaphylaxis, the COVID Vaccine Link & Diagnosis
Laxative allergy is most commonly caused by polyethylene glycol (PEG/macrogol), the osmotic agent in MiraLAX and colonoscopy bowel preps — and the same molecule used in Pfizer-BioNTech and Moderna COVID-19 mRNA vaccine lipid nanoparticles. Patients average three anaphylaxis episodes before PEG is identified as the culprit. True allergy to other laxative classes is rare. PEG-free colonoscopy alternatives include SUPREP and Sutab.
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Key facts
Patients with PEG anaphylaxis averaged three separate anaphylaxis episodes before PEG was correctly identified as the culprit (Stone et al., J Allergy Clin Immunol Pract, 2019).
PEG appears in MiraLAX, colonoscopy bowel preparations (GoLytely, MoviPrep), and Pfizer-BioNTech/Moderna COVID-19 mRNA vaccine lipid nanoparticles — delayed PEG identification explains reactions across unrelated products.
Three of 10 PEG-allergic patients cross-sensitize to polysorbate 80 through the shared polyether backbone — relevant because polysorbate 80 is used in biologic medications and vaccines.
PEG-free colonoscopy alternatives include SUPREP (sodium sulfate-based) and Sutab (tablets) — important options for patients with confirmed PEG allergy requiring bowel preparation.
What Is Laxative Allergy?
Laxative allergy refers to immune-mediated hypersensitivity reactions triggered by components of laxative medications, most significantly polyethylene glycol (PEG/macrogol) — the osmotic agent in MiraLAX, GoLytely, and other bowel preparations.
PEG-mediated anaphylaxis is the dominant modern laxative allergy entity, characterized by IgE antibodies targeting the polyether backbone of PEG molecules. Stone et al. demonstrated in their foundational 2019 study in the Journal of Allergy and Clinical Immunology in Practice that patients averaged three separate anaphylaxis episodes before PEG was correctly identified as the culprit, because the molecule appears as an excipient in seemingly unrelated products.
Laxatives as a class span five mechanistic subfamilies: bulk-forming (psyllium, methylcellulose), osmotic (PEG, lactulose, magnesium), stimulant (senna, bisacodyl), surfactant (docusate), and lubricant (mineral oil). While any drug can theoretically cause hypersensitivity, the allergy signal is overwhelmingly concentrated in PEG-containing osmotic laxatives and, to a lesser extent, in anthraquinone-containing stimulant laxatives that cause allergic contact dermatitis. Docusate and lactulose allergy is virtually unreported in the medical literature.
The clinical significance of PEG as a hidden allergen extends well beyond laxative use. PEG is found in colonoscopy bowel preparation solutions (GoLytely, CoLyte, NuLYTELY, MoviPrep, Plenvu), depot injectable medications, many oral tablet coatings, and critically in the lipid nanoparticle coating of Pfizer-BioNTech and Moderna COVID-19 mRNA vaccines which contain PEG 2000. Patients averaging three anaphylactic episodes before PEG allergy is recognized illustrates how the ubiquity of PEG across unrelated products delays diagnosis.
Laxative Allergy Symptoms
Recognizing symptoms early helps you get the right treatment faster.
Anaphylaxis
severeSevere, potentially life-threatening systemic reaction with hypotension, airway compromise, and cardiovascular collapse occurring within minutes of PEG exposure.
Urticaria (hives)
moderateWidespread itchy, raised welts appearing within minutes to an hour after ingesting PEG-containing products or other laxative components.
Angioedema
severeDeep swelling of the face, lips, tongue, or throat that can compromise the airway. Often accompanies urticaria in PEG reactions.
Bronchospasm
severeWheezing, chest tightness, and difficulty breathing caused by airway constriction during a PEG-mediated allergic reaction or from psyllium inhalation.
Nausea and vomiting
moderateGastrointestinal symptoms that may accompany systemic PEG reactions and can be mistaken for simple intolerance to the bowel preparation.
Contact dermatitis (anthraquinone)
mildItchy, erythematous skin rash at the site of contact with senna, cascara, or aloe vera-containing laxative preparations. Delayed onset (24-72 hours).
Occupational rhinitis and asthma
moderateSneezing, nasal congestion, wheezing, and cough in healthcare workers exposed to aerosolized psyllium powder during medication preparation.
Hypotension
severeDangerous drop in blood pressure during systemic anaphylaxis to PEG, manifesting as dizziness, lightheadedness, or loss of consciousness.
When to see a doctor
PEG anaphylaxis is the most severe presentation of laxative allergy and can be fatal without immediate treatment. Symptoms typically develop within minutes to one hour of PEG ingestion or injection. Because PEG appears in many seemingly unrelated products, patients often experience multiple unexplained anaphylaxis events before the common excipient is identified — Stone et al. documented an average of three reactions before diagnosis. Anthraquinone contact dermatitis from senna or cascara presents as a delayed skin reaction at the application site. Psyllium-induced occupational asthma presents with respiratory symptoms during workplace exposure to bulk powder. If you experience difficulty breathing, throat tightening, widespread hives, or dizziness after taking any laxative, seek emergency medical care immediately.
Can Laxative Allergy Trigger Asthma?
PEG-mediated anaphylaxis can include severe bronchospasm as part of the systemic allergic reaction, but PEG laxatives do not typically cause chronic asthma. The more specific asthma connection involves psyllium (Metamucil) occupational exposure — Malo et al. documented IgE-mediated occupational asthma in pharmacy and healthcare workers handling bulk psyllium powder, a well-established occupational allergen model. Additionally, metabisulfite preservatives present in some laxative formulations may trigger bronchospasm in sulfite-sensitive asthmatic patients, who represent approximately 5% of the asthmatic population. If you have asthma and experience worsening respiratory symptoms after taking a laxative, consult your allergist to evaluate for sulfite sensitivity or PEG-specific IgE.
Complications of Unrecognized Laxative Allergy
The most significant complication of unrecognized PEG allergy is the risk of repeated life-threatening anaphylaxis. Because PEG is a hidden excipient in hundreds of pharmaceutical products, patients without a confirmed PEG allergy diagnosis face unpredictable exposure. Stone et al.'s 2019 finding that patients averaged three anaphylaxis episodes before diagnosis underscores this danger. The COVID-19 vaccination landscape added a critical dimension — confirmed PEG allergy became a contraindication to Pfizer-BioNTech and Moderna mRNA vaccines, with the J&J (Janssen) and Novavax vaccines serving as PEG-free alternatives. Failure to identify PEG sensitization could also complicate future surgical procedures requiring PEG-based bowel preparation for colonoscopy. If you have experienced unexplained anaphylaxis more than once, discuss PEG allergy evaluation with a board-certified allergist. Psyllium occupational anaphylaxis represents a distinct laxative allergy entity, documented in pharmacy and healthcare workers who handle bulk psyllium powder during dispensing operations. Inhalation of airborne psyllium particles can trigger classical occupational asthma and IgE-mediated anaphylaxis in sensitized workers. Bisacodyl hypersensitivity, though rare, has been reported in case studies presenting as urticaria, anaphylaxis, and fixed drug eruption. Lactulose and docusate, by contrast, have virtually no documented allergic hypersensitivity in the published literature.
Recurrent unexplained anaphylaxis
Patients with undiagnosed PEG allergy face repeated life-threatening reactions to seemingly unrelated products sharing the PEG excipient.
Unsafe colonoscopy preparation
Using PEG-based bowel preparations (GoLytely, NuLYTELY) in undiagnosed PEG-allergic patients can trigger anaphylaxis during pre-procedure preparation.
COVID-19 vaccination complications
Unrecognized PEG allergy increases the risk of anaphylaxis to mRNA COVID-19 vaccines containing PEG 2000 in their lipid nanoparticle formulation.
Diagnostic delay
The average three-reaction delay before PEG diagnosis means patients may undergo unnecessary workups for other conditions while the true culprit remains unidentified.
What Causes Laxative Allergy?
PEG IgE-mediated anaphylaxis is the primary cause of clinically significant laxative allergy. PEG is a water-soluble polyether polymer used in MiraLAX (PEG 3350), colonoscopy bowel preparations (GoLytely, CoLyte, NuLYTELY, MoviPrep, Plenvu), injectable depot formulations, tablet coatings, and critically in the lipid nanoparticle shell of Pfizer-BioNTech and Moderna COVID-19 mRNA vaccines (PEG 2000). Sensitization can develop after any PEG exposure, making the clinical trail difficult to trace across multiple unrelated products.
How it works
PEG anaphylaxis follows the classical Type I IgE-mediated pathway. PEG molecules act as multivalent antigens capable of cross-linking IgE bound to mast cell and basophil FcepsilonRI receptors, triggering immediate degranulation with release of histamine, tryptase, prostaglandins, and leukotrienes. PEG-specific IgE is detectable in confirmed cases via serum assays and skin testing with graded molecular weights. Anthraquinone contact dermatitis follows a Type IV T-cell-mediated delayed hypersensitivity pathway. Melanosis coli from chronic anthraquinone use is lipofuscin pigment deposition in colonic macrophages — it is NOT an allergic process.
Polysorbate 80 cross-reactivity compounds the diagnostic challenge — Wenande and Garvey's 2016 review in Clinical and Experimental Allergy documented that 3 of 10 PEG-allergic patients cross-sensitize to polysorbate 80 because of their shared polyether backbone motif. Anthraquinone stimulant laxatives (senna, cascara, aloe vera preparations) can cause Type IV allergic contact dermatitis confirmed by patch testing. Bisacodyl hypersensitivity presents as rare urticaria, anaphylaxis, or fixed drug eruption. Psyllium (Metamucil) causes IgE-mediated occupational asthma and anaphylaxis in pharmacy and healthcare workers who handle bulk powder, making it a well-documented occupational allergen.
PEG-specific IgE antibodies have been detected in confirmed cases through both serum assays and stepwise skin testing. Cross-reactivity with polysorbate 80 has been documented in 3 of 10 PEG-allergic patients tested, reflecting the shared polyether backbone motif between these structurally related excipients. This cross-reactivity has clinical implications because polysorbate 80 is used as a stabilizer in numerous biologic medications, vaccines (including the Johnson and Johnson COVID-19 vaccine), and food products. Anthraquinone laxatives including senna and cascara can cause Type IV allergic contact dermatitis, which should be distinguished from melanosis coli — a cosmetic pigmentation of the colonic mucosa caused by lipofuscin deposits in mucosal macrophages that is not an allergic phenomenon.
Risk factors to watch for
Prior unexplained anaphylaxis to multiple products
Patients who have had anaphylaxis to seemingly unrelated products containing PEG as an excipient may have unrecognized PEG sensitization.
Colonoscopy bowel prep reactions
Reactions during colonoscopy preparation with PEG-based solutions (GoLytely, CoLyte) are a common clinical presentation.
COVID-19 mRNA vaccination reaction
Anaphylaxis following Pfizer-BioNTech or Moderna vaccination may indicate PEG sensitization, given PEG 2000 in the lipid nanoparticle shell.
Healthcare worker psyllium exposure
Pharmacy and nursing staff who handle bulk psyllium (Metamucil) powder are at risk for occupational IgE-mediated respiratory sensitization.
The Allergy Cascade
Exposure
Allergen contact
Detection
Immune recognition
IgE Response
Antibody production
Mast Cells
Histamine release
Symptoms
Allergic reaction
1.Exposure
Allergen contact
2.Detection
Immune recognition
3.IgE Response
Antibody production
4.Mast Cells
Histamine release
5.Symptoms
Allergic reaction
Diagnosing Laxative Allergy
PEG allergy diagnosis requires stepwise skin testing with PEG solutions of varying molecular weights, performed exclusively in a facility equipped for anaphylaxis management. This is a critical safety point — Stone et al. reported a 25% systemic reaction rate during PEG skin testing itself. The stepwise protocol begins with PEG 300 and progresses through PEG 1500, 3350, and 4000 using prick-then-intradermal technique. PEG-specific serum IgE assays can support the diagnosis. Polysorbate 80 skin testing should be performed concurrently given the documented cross-reactivity. For anthraquinone contact dermatitis from senna or cascara, standard epicutaneous patch testing with the specific laxative component is diagnostic. For at-home evaluation of concurrent IgE-mediated environmental allergies such as dust mites, pollens, or pet dander, services like Curex offer at-home allergy testing panels covering 40+ allergens with results typically within 5 days and insurance accepted. However, PEG and polysorbate 80 sensitization require in-clinic evaluation by a board-certified allergist. Skin testing for PEG allergy employs a stepwise approach using PEG solutions of varying molecular weights — PEG 300, 1500, 3350, and 4000 — administered as skin prick followed by intradermal injection at each molecular weight before proceeding to the next. This protocol carries a 25% systemic reaction rate during the testing procedure itself, mandating that testing be performed only in facilities fully equipped for anaphylaxis management with immediate access to epinephrine, intubation equipment, and resuscitation capabilities.
Stepwise PEG Skin Testing
Graded prick-then-intradermal testing with PEG solutions of increasing molecular weights (300, 1500, 3350, 4000). Must be performed in a facility equipped for anaphylaxis management due to the 25% systemic reaction rate during testing.
PEG-Specific Serum IgE
Blood test measuring circulating IgE antibodies directed against polyethylene glycol. Supports the clinical diagnosis alongside skin testing.
Polysorbate 80 Skin Testing
Concurrent prick and intradermal testing with polysorbate 80 to evaluate cross-reactivity, given that 3 of 10 PEG-allergic patients cross-sensitize to polysorbate 80.
Patch Testing for Anthraquinone Contact Dermatitis
Standard epicutaneous patch testing with senna, cascara, or aloe vera extracts applied to the back and read at 48 and 96 hours to diagnose Type IV contact allergy to stimulant laxatives.
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The long-term solution to allergies
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Unlike hay fever or dust mite asthma, PEG anaphylaxis and laxative allergy cannot be treated with allergen-specific immunotherapy — there is no established desensitization protocol for PEG, and sublingual or subcutaneous immunotherapy targets IgE-mediated environmental allergens rather than drug excipients. The management of laxative allergy is strictly avoidance-based combined with emergency preparedness. However, many patients with drug allergies also have concurrent environmental allergies — dust mites, pollens, pet dander, molds — that contribute to their overall allergic burden. Sublingual immunotherapy (SLIT) can address these environmental triggers. Providers like Curex offer at-home SLIT drops starting at $39/month that target IgE-mediated respiratory allergies, eliminating the weekly clinic visits required for traditional allergy shots. For drug allergy evaluation itself, including PEG skin testing, you will need to see a board-certified allergist in a facility equipped for anaphylaxis management. While immunotherapy does not address PEG sensitization, patients with multiple unexplained anaphylaxis episodes may benefit from comprehensive environmental allergy evaluation to identify concurrent IgE-mediated triggers that could confound the diagnostic picture.
Confirm PEG Sensitization
Undergo stepwise PEG skin testing with an allergist in a facility equipped for anaphylaxis management. Concurrent polysorbate 80 testing is recommended.
Identify All PEG-Containing Products
Work with your pharmacist to review all current medications, supplements, and personal care products for PEG and polysorbate 80 content.
Establish Alternatives
Document PEG-free alternatives for laxatives, bowel preparations, and other needed medications. Alert all healthcare providers to your PEG allergy.
Address Environmental Allergies Separately
If you also have IgE-mediated respiratory allergies, discuss sublingual immunotherapy with your allergist as a separate treatment track from your PEG avoidance plan.
“PEG avoidance effectively prevents reactions when all sources are identified; immunotherapy for concurrent environmental allergies shows 60-85% symptom reduction in clinical trials”
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Living With Laxative Allergy
Living with PEG allergy requires ongoing vigilance because polyethylene glycol is one of the most widely used excipients in the pharmaceutical industry. The initial adjustment involves a comprehensive review of all medications, supplements, and personal care products with your pharmacist. Many patients find it helpful to maintain a wallet card listing their specific allergens (PEG, polysorbate 80 if cross-reactive) to present at every healthcare encounter. The emotional impact of PEG allergy should not be underestimated — particularly for patients who experienced multiple unexplained anaphylaxis episodes before diagnosis. Working with an allergist who understands excipient allergies provides both medical management and reassurance that the condition is now identified and manageable.
Building a PEG-Free Medicine Cabinet
Work with your pharmacist to identify PEG-free alternatives for all routine medications. Keep a written list of safe products and share it with all healthcare providers. Many generic medications use PEG in tablet coatings — brand formulations may differ.
Preparing for Medical Procedures
Before any surgery, colonoscopy, or medical procedure, alert the team to your PEG allergy in writing. Specify PEG-free bowel preparation, PEG-free surgical scrub, and PEG-free injectable vehicles.
Vaccination Planning
Discuss vaccine formulations with your allergist before each vaccination. mRNA COVID-19 vaccines contain PEG 2000; other vaccine formulations may contain polysorbate 80. Your allergist can determine which vaccines are safe for you.
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Prevention Tips
Carry a Medical Alert for PEG Allergy
Wear a medical alert bracelet or carry a card specifying PEG and polysorbate 80 allergy. This is critical for emergency situations and surgical settings.
Review Medication Excipients with Your Pharmacist
Have your pharmacist screen all prescription and OTC medications for PEG content before dispensing. PEG appears in tablet coatings, liquid suspensions, and injectable vehicles.
Specify PEG-Free Bowel Prep Before Colonoscopy
Alert your gastroenterologist to use SUPREP, Sutab, or Prepopik/Clenpiq rather than GoLytely or other PEG-based bowel preparations.
Carry Epinephrine at All Times
All patients with confirmed PEG anaphylaxis should carry two epinephrine auto-injectors and know how to use them. Replace before expiration dates.
Alert Vaccination Providers
Before any vaccination, inform your provider about PEG allergy. mRNA COVID-19 vaccines (Pfizer, Moderna) contain PEG 2000; PEG-free alternatives exist.
Outlook for Laxative Allergy
PEG allergy is a lifelong sensitization — once PEG-specific IgE develops, it persists, and future PEG exposure carries anaphylaxis risk. The good news is that with proper diagnosis and comprehensive avoidance, patients with PEG allergy can live safely and manage constipation effectively with PEG-free alternatives. The recognition of PEG as a significant hidden allergen has improved substantially since Stone et al.'s 2019 publication and the COVID-19 vaccination experience, meaning that allergists are now much more attuned to PEG allergy testing. Patients diagnosed today are likely to have shorter diagnostic delays than the historical average of three anaphylaxis episodes before identification.
Key takeaways
PEG sensitization is lifelong, but strict avoidance prevents reactions effectively
PEG-free colonoscopy preparations (SUPREP, Sutab, Prepopik) provide safe alternatives for necessary procedures
Improved clinical awareness since 2019-2021 means faster diagnosis and fewer missed PEG allergy cases
Diet and Laxative Allergy
Dietary factors do not directly cause laxative allergy, but diet plays a central role in reducing the need for laxative medications in the first place — which minimizes exposure risk for sensitized individuals. High-fiber diets, adequate hydration, and regular physical activity are the cornerstones of non-pharmacologic constipation management. For PEG-allergic patients, it is worth noting that PEG can appear in some food-grade coatings and emulsifiers, though at levels unlikely to trigger reactions in most sensitized individuals. If you have confirmed severe PEG allergy, discuss dietary sources with your allergist.
Foods that help
High-fiber fruits and vegetables
Natural dietary fiber promotes regular bowel movements and reduces dependence on laxative medications.
Prunes and prune juice
Contains sorbitol and fiber, acting as a natural osmotic and bulk-forming laxative without PEG exposure.
PEG allergy is the hidden allergen story of the past decade — it is in MiraLAX, colonoscopy prep, and the mRNA COVID vaccines. Patients reacting to seemingly unrelated products often share PEG. Three anaphylaxis episodes before diagnosis is unacceptable, and I now screen for PEG allergy in unexplained recurrent anaphylaxis when no food or drug trigger is identified.
Frequently Asked Questions
Yes, you can be allergic to MiraLAX. MiraLAX contains polyethylene glycol 3350 (PEG 3350), and IgE-mediated allergy to PEG is a well-documented clinical entity. Reactions can range from urticaria and angioedema to life-threatening anaphylaxis. Stone et al. published a foundational 2019 study in the Journal of Allergy and Clinical Immunology in Practice showing that PEG is an under-recognized cause of recurrent anaphylaxis. If you experience hives, swelling, difficulty breathing, or dizziness after taking MiraLAX, discontinue the product and consult an allergist who can perform PEG-specific skin testing.
PEG molecules in laxatives (PEG 3350) and in COVID-19 mRNA vaccines (PEG 2000) share the same polyether backbone structure, which is the target of PEG-specific IgE antibodies. The molecular weight differs — PEG 3350 in MiraLAX is larger than PEG 2000 in vaccine lipid nanoparticles — but IgE cross-reactivity across PEG molecular weights is well documented. The CDC and AAAAI issued joint guidance in late 2020 stating that confirmed PEG allergy is a contraindication to Pfizer-BioNTech and Moderna mRNA vaccines. PEG-free vaccine alternatives (J&J Janssen, Novavax) were recommended for these patients.
Three FDA-approved PEG-free colonoscopy bowel preparations are available for PEG-allergic patients: SUPREP (sodium sulfate, potassium sulfate, and magnesium sulfate in solution), Sutab (sodium sulfate tablets), and Prepopik or Clenpiq (sodium picosulfate with magnesium citrate). These preparations achieve comparable bowel cleansing quality to PEG-based solutions in clinical trials. You should inform your gastroenterologist about your PEG allergy before scheduling a colonoscopy so that the PEG-free preparation can be prescribed and any other PEG-containing products in the procedure protocol can be eliminated.
Laxative intolerance involves pharmacologic side effects — cramping, bloating, diarrhea, electrolyte disturbances — that are expected dose-dependent effects of the medication, not immune-mediated reactions. These affect many users and resolve with dose adjustment or switching to a different laxative class. Laxative allergy, by contrast, is an immune-mediated hypersensitivity reaction (IgE-mediated for PEG, Type IV for anthraquinone contact dermatitis) that can cause urticaria, angioedema, or anaphylaxis regardless of dose. The distinction matters clinically because true PEG allergy requires complete avoidance, while intolerance can often be managed by adjusting the dose or switching products.
Melanosis coli is not an allergic reaction. It is a benign pigmentation of the colonic mucosa caused by chronic use of anthraquinone-containing stimulant laxatives such as senna (Senokot) and cascara. The dark pigment is lipofuscin deposited in macrophages within the colonic wall, resulting from apoptosis of colonic epithelial cells — a pharmacologic process, not an immune-mediated one. Melanosis coli is typically reversible within months of discontinuing the anthraquinone laxative. If you are concerned about colonic discoloration found during colonoscopy, discuss it with your gastroenterologist, but it does not indicate allergy.
Yes, healthcare workers and pharmacists who handle bulk psyllium powder (Metamucil) can develop IgE-mediated occupational sensitization through repeated aerosol inhalation. Malo et al. published documentation of occupational asthma in pharmacy and hospital workers exposed to aerosolized psyllium particles during medication preparation and dispensing. Symptoms include rhinitis, conjunctivitis, cough, wheezing, and in severe cases anaphylaxis on subsequent exposures. This is a well-characterized occupational asthma model. Workers who notice respiratory symptoms during psyllium handling should use respiratory protection, consult occupational medicine for specific IgE testing, and discuss workplace accommodations with their employer.
PEG allergy skin testing follows a stepwise molecular-weight protocol performed exclusively in a facility equipped for anaphylaxis management. The allergist begins with PEG 300 (lowest molecular weight), then progresses to PEG 1500, 3350, and 4000, using prick testing followed by intradermal testing at each molecular weight. Stone et al. documented a 25% systemic reaction rate during PEG skin testing itself, making this a procedure that requires IV access, epinephrine, and resuscitation equipment at bedside. Concurrent polysorbate 80 skin testing is recommended to evaluate cross-reactivity. A negative skin test does not definitively rule out allergy.
Magnesium-based osmotic laxatives such as milk of magnesia (magnesium hydroxide) and magnesium citrate do not cause allergic reactions in any clinically significant sense. The toxicity from magnesium-based laxatives — hypermagnesemia leading to hypotension, respiratory depression, and cardiac arrest — is a pharmacologic overdose effect that occurs almost exclusively in patients with renal impairment who cannot excrete the absorbed magnesium. This is a dose-dependent poisoning phenomenon, not an immune-mediated allergy. Patients with normal kidney function tolerate standard doses safely, but magnesium laxatives should be used cautiously in patients with chronic kidney disease.
Medical References
- [1]Stone CA Jr, Liu Y, Relling MV, et al. Immediate hypersensitivity to polyethylene glycols and polysorbates: More common than we have recognized. J Allergy Clin Immunol Pract. 2019;7(5):1533-1540.e8.
- [2]Wenande E, Garvey LH. Immediate-type hypersensitivity to polyethylene glycols: A review. Clin Exp Allergy. 2016;46(7):907-922.
- [3]Khan DA, Banerji A, Blumenthal KG, et al. Drug allergy: A 2022 practice parameter update. J Allergy Clin Immunol. 2022;150(6):1333-1393.
- [4]CDC/ACIP. Interim Clinical Considerations for Use of COVID-19 Vaccines: Appendix B — Contraindications and precautions for PEG and polysorbate. Centers for Disease Control and Prevention. Updated 2021.
- [5]Malo JL, Cartier A, L'Archeveque J, et al. Prevalence of occupational asthma and immunologic sensitization to psyllium among health personnel in chronic care hospitals. Am Rev Respir Dis. 1990;142(6 Pt 1):1359-1366.
- [6]American Academy of Allergy, Asthma and Immunology (AAAAI). Polyethylene glycol (PEG) allergy: clinical guidance for COVID-19 vaccination. AAAAI.org. 2021.
This content is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about a medical condition. Content reviewed by board-certified allergists at Curex.
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