Medicines to Avoid if You Have an Aspirin or NSAID Sensitivity: A Guide for Patients.

People who react to aspirin and have aspirin sensitivity often also react to other non‑steroidal anti‑inflammatory drugs (NSAIDs) such as ibuprofen, naproxen, or diclofenac. This is because many NSAIDs work in a similar way in the body.

This page summarises the medicines you should usually avoid, medicines that may be options only under specialist advice, and how to check products safely.

1. Why reactions happen

Some people are sensitive to medicines that strongly block the COX‑1 enzyme (for example aspirin, ibuprofen, naproxen, diclofenac). This can trigger breathing symptoms, sinus problems, hives, swelling, or other reactions.

There are two main patterns:

Cross‑reactive sensitivity: reactions to several different NSAIDs.
Selective allergy: reaction to one specific NSAID only.

Your doctor or allergy specialist can tell you which applies to you.

2. Medicines you should usually avoid

Unless a specialist has advised otherwise, avoid medicines containing the following active ingredients:

Aspirin (acetylsalicylic acid)

Found in many painkillers and cold/flu remedies.

Common NSAIDs

Ibuprofen
Naproxen
Diclofenac
Indometacin
Ketoprofen
Ketorolac
Mefenamic acid
Piroxicam
Tenoxicam
Sulindac
Etodolac
Nabumetone
Flurbiprofen
Fenoprofen
Fenbufen
Tolfenamic acid
Tiaprofenic acid

Important: Brand names change frequently. Always check the active ingredient on the label.

3. Medicines that may be options under specialist advice

Some people with aspirin/NSAID sensitivity can tolerate medicines that mainly block COX‑2, such as:

Celecoxib
Etoricoxib
Parecoxib

These medicines can still cause reactions in some patients and carry cardiovascular risks. They should only be used if recommended by a specialist.

4. Medicines that are often safe

Paracetamol (acetaminophen) is usually safe at standard doses. A small number of people may react at high doses, so follow the label and speak to your doctor if you have reacted before.
If you have a selective allergy (e.g., only to ibuprofen), your specialist may confirm that other NSAIDs are safe for you. Do not test this yourself.

5. How to check medicines safely

Always read the active ingredient list on painkillers, cold/flu remedies, and over‑the‑counter products.
Tell your pharmacist, GP, dentist, and any hospital team about your aspirin/NSAID sensitivity.
If unsure, ask a pharmacist before taking a new medicine.

6. Additional reliable sources

These provide up‑to‑date, trustworthy information:

NHS – NSAIDs overview https://www.nhs.uk/conditions/nsaids/
NICE Clinical Knowledge Summary – NSAIDs https://cks.nice.org.uk/topics/nsaids-prescribing-issues/ (cks.nice.org.uk in Bing)
Allergy UK – Aspirin Intolerance https://www.allergyuk.org/resources/aspirin-intolerance-and-salicylates/ (allergyuk.org in Bing)
BSACI – NSAID Hypersensitivity (clinical guideline) https://www.bsaci.org/guidelines-and-standards/bsaci-guidelines/ (bsaci.org in Bing)

Last reviewed: February 2026