Category: For General Public

Information for general public

Game Changer: FDA Approves Rhapsido (Remibrutinib), the First Oral BTK Inhibitor for Chronic Hives (CSU)

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FDA approval of Rhapsido (remibrutinib), the first oral BTK inhibitor pill for chronic spontaneous urticaria (CSU).

For years, patients with chronic spontaneous urticaria (CSU) who didn’t respond to antihistamines had only injections as the next step. On September 30, 2025, the U.S. Food and Drug Administration (FDA) approved remibrutinib (brand name Rhapsido), the first oral BTK inhibitor for adults with CSU. This approval offers patients — and doctors — the first convenient oral option beyond antihistamines. What Is Chronic Spontaneous Urticaria (CSU)? Why an Oral Option Matters Until now, patients had only these alternatives: Patients have long asked for a safe oral treatment that avoids injections…

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Drug vs Food Allergy: Immediate & Delayed Reactions

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Infographic comparing drug vs food allergy: immediate (anaphylaxis) and delayed reactions; SJS/TEN uncommon with food.

Drug vs Food Allergy: Why Medications Can Cause Both Immediate and Delayed Reactions — While Foods Uncommonly Cause Severe Delayed Reactions This article is for educational purposes only. Always consult healthcare providers for personalized medical advice. Patients often ask:“Why can medications cause both rapid allergic reactions like hives or anaphylaxis and dangerous delayed reactions such as Stevens–Johnson Syndrome (SJS) or Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), while food allergies almost always appear immediately?” The difference lies in how the immune system processes drugs versus foods — and in…

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Sulfa Allergy: Safe Drugs, Drugs to Avoid, and How to Think About Cross-Reactivity

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Infographic on sulfa allergies showing safe versus avoid drug lists, including furosemide, HCTZ, sulfonylureas, celecoxib, etoricoxib, and high-risk drugs like sulfamethoxazole, sulfadiazine, sulfasalazine, and dapsone.

Many patients search online for sulfa allergy safe drugs after experiencing severe reactions to antibiotics such as co-trimoxazole (trimethoprim-sulfamethoxazole). When people hear the term “sulfa allergy,” confusion often follows. Some patients wonder if they must avoid every drug with “sulfa” in the name. The truth is: not all sulfa-containing medications are dangerous. The key is understanding the chemical structure—specifically whether the drug contains the N4 arylamine group. The Real Culprit: The N4 Arylamine Group The allergy risk in sulfonamide antibiotics comes from a specific chemical feature known as the N4…

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FDA Warns of Severe Rebound Itching After Stopping Cetirizine (Zyrtec) or Levocetirizine (Xyzal): What You Need to Know

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🛑 New FDA Safety Alert: Antihistamine Withdrawal Can Trigger Severe Itching In May 2025, the U.S. Food and Drug Administration (FDA) issued a new safety warning about rebound itching after stopping cetirizine (Zyrtec) or levocetirizine (Xyzal)—two of the most commonly used antihistamines. This severe itching reaction, often mistaken for allergy relapse, may occur especially in people who have taken the drug daily for several months. 🔎 Key Findings from the FDA Investigation Between April 2017 and July 2023, the FDA identified 209 confirmed cases globally—197 in the U.S.—involving moderate to…

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Sebetralstat: The First Oral Treatment for HAE Approved by FDA

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sebetralstat

Oral HAE treatment is now FDA-approved. On July 7, 2025, Sebetralstat (Ekterly®) became the first oral on-demand therapy for acute attacks in hereditary angioedema (HAE), marking a major shift in how this rare condition is managed. Hereditary Angioedema (HAE) is a rare genetic disorder that causes unpredictable, recurrent episodes of swelling, often affecting the face, throat, gastrointestinal tract, and extremities. If untreated, these attacks can be life-threatening. Until recently, on-demand treatment for HAE required injections only. While berotralstat (Orladeyo®) became the first oral medication approved for prophylaxis in 2020, acute…

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The Basophil Activation Test (BAT): A Game-Changing Tool for Food Allergy Diagnosis

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Basophil Activation Test (BAT) in Food Allergy

Diagnosing food allergies accurately remains one of the biggest challenges in allergy medicine. Traditional approaches like skin prick tests (SPT) and specific IgE blood tests can tell us if someone is sensitized to a food, but they don’t always predict whether that person will actually have an allergic reaction. Meanwhile, oral food challenges (OFCs)—the gold standard—are time-consuming, expensive, and carry real risks of severe reactions. Enter the Basophil Activation Test (BAT): a revolutionary diagnostic tool that’s changing how we approach food allergy diagnosis. 🧪 What Makes BAT Different? BAT is…

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Rethinking Drug Allergy Management: Finding Balance Between Caution and Access in SCARs

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Drug allergies present a complex landscape, demanding tailored management strategies based on the reaction’s nature and severity. We’ve witnessed significant progress in “de-labeling” allergies to common drugs like penicillin through careful testing, allowing many to safely access essential treatments. However, the approach to severe cutaneous adverse reactions (SCARs) – encompassing Stevens-Johnson Syndrome (SJS), Toxic Epidermal Necrolysis (TEN), Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), and Acute Generalized Exanthematous Pustulosis (AGEP) – often stands in stark contrast: a broad and often indefinite avoidance of all potentially implicated drugs. While the…

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Seafood Allergy: Causes, Symptoms, Diagnosis, and Prevention

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Seafood allergies are a serious and potentially life-threatening condition affecting millions worldwide. Whether you’re allergic to fish, shellfish, or both, understanding the causes, symptoms, and prevention strategies is crucial for managing your allergy safely. This comprehensive guide will cover everything you need to know about seafood allergies, including diagnosis, myths, and emergency preparedness. What Causes Seafood Allergies? Seafood allergies occur when the immune system mistakenly identifies certain proteins in fish or shellfish as harmful, triggering an allergic reaction. The primary allergens are: Fish vs. Shellfish Allergies: What’s the Difference? Symptoms…

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Understanding Angioedema: What You Need to Know

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tongue angioedema

What is Angioedema? Angioedema is a medical condition characterized by the rapid swelling of the deeper layers of the skin and mucous membranes. This swelling occurs due to the accumulation of fluid, leading to significant tissue expansion. The condition most commonly affects regions of the body such as the face, especially around the eyes and lips, the throat, hands, and feet. Unlike typical allergic reactions that often manifest with hives and intense itching, angioedema is distinguished by its deeper swelling and the absence of pruritus, or itchiness. This distinction can…

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Chronic Rhinitis Misconceptions: What You Need to Know

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Do you constantly reach for tissues, battle a stuffy nose, or wake up with unexplained headaches? You might be dealing with chronic rhinitis—but how much do you really know about this condition? Unfortunately, many chronic rhinitis misconceptions can lead to ineffective treatments and prolonged discomfort. Let’s set the record straight and uncover the truth about this common but often misunderstood condition. Misconception: Chronic Rhinitis Is Just a Runny Nose Many people think chronic rhinitis is no more than a minor annoyance, but the reality is far more complex. Chronic rhinitis…

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