What are the adverse effects of taking a low-dose Aspirin (acetylsalicylic acid) in individuals with an Aspirin allergy?

From the Guidelines

If you have an aspirin allergy, you should not take baby aspirin as it can cause serious allergic reactions. Even low-dose baby aspirin (typically 81 mg) contains the same active ingredient, acetylsalicylic acid, that triggers allergic responses. Potential side effects of taking baby aspirin with an allergy range from mild symptoms like hives, itching, and nasal congestion to severe reactions including difficulty breathing, swelling of the face or throat, and anaphylaxis, which can be life-threatening. These reactions occur because your immune system identifies aspirin as a harmful substance and releases chemicals that cause inflammation and other symptoms. Some key points to consider include:

• Aspirin allergy can manifest as unexpected respiratory symptoms or combined respiratory and cutaneous reactions, as noted in a 2022 practice parameter update 1.
• Patients with a history of NSAID reactions may be at risk for severe cutaneous adverse drug reactions, such as SJS/TEN, which can be life-threatening 1.
• A challenge is preferred over desensitization in patients with a remote history of an NSAID reaction and no AERD or active urticaria, as it is simpler and more efficient 1. If you need antiplatelet therapy or pain relief, consult your doctor about alternatives such as clopidogrel, ticagrelor, or non-NSAID pain relievers like acetaminophen. Never attempt to take even a small amount of aspirin if you have a known allergy, as sensitivity doesn't necessarily depend on dose. If you accidentally take aspirin and experience symptoms, seek immediate medical attention. It's also important to note that aspirin therapy may be considered as a primary prevention strategy in those with type 1 or type 2 diabetes who are at increased cardiovascular risk, but this should be done under the guidance of a healthcare provider and with careful consideration of the potential risks and benefits 1.

From the FDA Drug Label

Aspirin may cause a severe allergic reaction which may include: hives, facial swelling, asthma(wheezing), shock Do not Use if you are allergic to aspirin or any other pain reliever/fever reducer Stop use and ask a doctor if an allergic reaction occurs.

The side effects of taking a baby aspirin if you have an allergy include:

• Severe allergic reaction
• Hives
• Facial swelling
• Asthma (wheezing)
• Shock 2, 2, 2

From the Research

Side Effects of Taking a Baby Aspirin with an Allergy

• Aspirin sensitivity is divided into two main subgroups: the bronchospastic and the urticaria/angioedema type 3
• Nonsteroid anti-inflammatory drugs (NSAID) cross-react with aspirin in aspirin-sensitive patients, which can lead to adverse effects such as asthma, rhinosinusitis, and nasal polyps 3, 4
• Desensitization to aspirin is possible, but should be carried out with caution in selected patients, as it can produce desensitization to NSAID and may increase the risk of anaphylaxis or anaphylactoid reactions 3, 4
• Acetaminophen and nonacetylated salicylic acid can cross-react with aspirin in a small number of aspirin-sensitive individuals, usually when large doses are administered 3

Types of Reactions

• Aspirin-exacerbated respiratory disease (AERD) is a condition that manifests as asthma, rhinosinusitis/nasal polyps, and sensitivity to aspirin and other cyclooxygenase-1 (COX-1)-inhibitor nonsteroidal anti-inflammatory drugs (NSAIDs) 5
• Urticaria and anaphylaxis are also possible reactions to aspirin in sensitive individuals 6, 4
• The pathogenesis of AERD remains unknown, but these patients have been shown to have multiple abnormalities in arachidonic acid metabolism and in cysteinyl leukotriene 1 receptors 5

Management and Treatment

• Aspirin desensitization can be achieved to improve both upper and lower respiratory symptoms for most patients with AERD, but should only be attempted in those with stable coronary artery disease 4, 5
• Treatment of AERD patients with antileukotriene medications has been helpful but not preferential when compared with non-AERD patients 5
• Patients with aspirin sensitivity can take up to 650 mg of acetaminophen for analgesic or antipyretic relief, and can also use weak COX-1 inhibitors, such as sodium salicylate or choline magnesium trisalicylate 5