Aspirin allergy
Aspirin sensitivity, sometimes with asthma and nasal polyps.
About aspirin allergy
Aspirin is a salicylate that relieves pain, lowers fever and, at low doses, thins the blood. Many reactions are not classic immune allergy but a pharmacological intolerance: aspirin blocks the COX-1 enzyme, shifting the body's chemistry towards inflammatory mediators, triggering symptoms without IgE antibodies. A recognised pattern, sometimes called aspirin-exacerbated respiratory disease, links aspirin sensitivity with asthma and nasal polyps. Because the mechanism is a drug-class effect, people affected this way often react to other NSAIDs too.
Reactions range from hives, facial swelling and worsening asthma with wheeze and a blocked or runny nose, through to, in some cases, anaphylaxis with rapid breathing difficulty and collapse, in keeping with the rapid onset described. Some people instead develop delayed skin rashes. The overlap across the whole NSAID family is important, because avoiding aspirin alone may not be enough if related painkillers provoke the same response.
Management rests on avoiding aspirin and, where advised, other NSAIDs, and on telling every doctor, dentist and pharmacist, since aspirin appears in many combination remedies. A medical alert can help. Specialist assessment can clarify whether the problem is true allergy or intolerance and identify safer options; in selected cases supervised desensitisation is used under expert care. A severe reaction is a medical emergency call 999. Never take, re-take or dose aspirin without professional advice.
Common triggers
- Aspirin and products containing it
Symptoms
- Skin rash, hives or itching
- Swelling of the face, lips or throat
- Wheezing or difficulty breathing
- Dizziness or a drop in blood pressure
- In severe cases, anaphylaxis
Avoidance & management
- Tell every doctor, pharmacist and dentist about the allergy
- Wear a medical-alert bracelet if advised
- Check the ingredients of combination medicines
- Discuss safe alternatives with your prescriber
- Seek emergency care for a severe reaction
Sources & references
Allergy safety: what everyone should know
Mild-to-moderate reaction signs
- Itching, hives or a raised rash
- Swelling of lips, face or eyes
- Tingling mouth, sneezing, runny nose
- Stomach pain, nausea or vomiting
Anaphylaxis — call 999 (UK) or 112 (EU) immediately
- Difficult or noisy breathing, wheeze, persistent cough
- Swelling of the tongue or tightness in the throat
- Dizziness, collapse, pale and floppy (young children)
- Use an adrenaline auto-injector (e.g. EpiPen) at once if prescribed, then call an ambulance even if symptoms improve
Allergy or intolerance? A true allergy involves the immune system and can escalate quickly; an intolerance (e.g. lactose intolerance) is unpleasant but not life-threatening. The symptoms overlap, so self-diagnosis is unreliable.
Getting tested: home-testing kits based on IgG are not diagnostically valid. If you suspect an allergy, ask a GP for referral to an allergy clinic for skin-prick or specific-IgE testing and a supervised food challenge where appropriate.