Around one in ten drug reactions happen due to an allergy.
The immune system overreacts to the medication and causes allergic symptoms. Intolerances or sensitivities to drugs can cause similar symptoms, but they do not involve the immune system.
Some medications cause allergic reactions more than others. The most common offenders include:
- Antibiotics, e.g., penicillin
- Non-steroidal anti-inflammatory drugs, e.g., ibuprofen
- Monoclonal antibody therapy – specialized injectable medications
Allergies to medication are more likely to develop when taken frequently, rubbed on skin, or taken via injection.