Signs and symptoms
 | Drug rash |
Signs and symptoms of a penicillin allergy include:
- Hives
- Rash
- Itchy skin
- Wheezing
- Swollen lips, tongue or face (angioedema)
Tell your doctor if you notice any of the signs or symptoms of penicillin allergy. He or she can determine if you're having an allergic reaction and may prescribe an alternate antibiotic.
Anaphylactic reactions
The most serious allergic reaction to penicillin is an anaphylactic (an-uh-fuh-LAK-tik) response, which can be life-threatening. Anaphylactic reactions develop immediately after penicillin exposure in highly sensitive people. Anaphylactic reactions cause the airways to constrict and low blood pressure. Signs and symptoms include:
- Constriction of the airways, including wheezing and a swollen tongue or throat, that results in difficulty breathing
- Shock associated with a marked decrease in blood pressure
- Weak and rapid pulse
- Dizziness or fainting
- Hives and itching
- Flushed or pale skin
- Nausea, vomiting or diarrhea
Seek emergency medical care if you think you or someone else is having an anaphylactic reaction.
