5 doctors weighed in:

How long does it take a rash due to a penicillin allergy to clear?

5 doctors weighed in
Dr. Alan Goldsobel
Internal Medicine - Allergy & Immunology
3 doctors agree

In brief: < 7 - 10 days

Antibiotics like penicillin can cause different types of rashes that can vary in how long they persist.
The classical true penicillin allergic rash is hives and once the penicillin is stopped usually resolves in less than 7-10 days. Occasionally this can trigger more prolonged hives. Other rashes from penicillin not due to true allergy would include small red bumps that usually lasts < 1-2 wks.

In brief: < 7 - 10 days

Antibiotics like penicillin can cause different types of rashes that can vary in how long they persist.
The classical true penicillin allergic rash is hives and once the penicillin is stopped usually resolves in less than 7-10 days. Occasionally this can trigger more prolonged hives. Other rashes from penicillin not due to true allergy would include small red bumps that usually lasts < 1-2 wks.
Dr. Alan Goldsobel
Dr. Alan Goldsobel
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Dr. Gary Steven
Internal Medicine - Allergy & Immunology

In brief: 3 to 10 days

Sometimes longer, if the reaction is severe, or you kept taking the penicillin for several days after the rash first appeared.

In brief: 3 to 10 days

Sometimes longer, if the reaction is severe, or you kept taking the penicillin for several days after the rash first appeared.
Dr. Gary Steven
Dr. Gary Steven
Thank
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