Drug allergy symptoms

Between 5-10% of people in the UK have a drug allergy, with these being the most common symptoms:

• rash  
• itchy face and eyes
• hives 
• wheeze
• facial swelling 
• anaphylaxis

This allergy could be to a drug your GP has prescribed for you or a drug you've been given in hospital, such as:

• penicillin and other antibiotics  
• aspirin and other non-steroidal anti-inflammatory drugs, such as ibuprofen
• anaesthetic drugs
• anti-convulsant drugs
• chemotherapy drugs

There are other substances that you could be allergic to such as the contrast dye used in X-rays or CT scanning. You could also have an allergy to the skin cleaning agents used in hospital and latex.

Confirming an allergic reaction

It is important to make sure that the reaction you have is actually an allergic reaction and not a side-effect of the medication, like feeling sick. We would ask you what symptoms you have and when they happen to help us know, but we may have to do more tests.

We may use skin testing as a way to check for allergic sensitisation to some drugs. If skin testing is not possible, or the result is unclear, we may get you to take the medication again, but under controlled conditions.

We do about six to ten drug challenges every month. This is to confirm if a drug was the cause of a reaction, but more often to identify safe alternatives.