4 doctors weighed in:

How long will hives last if i'm having an allergic reaction to medication?

4 doctors weighed in
Dr. Gary Steven
Internal Medicine - Allergy & Immunology
2 doctors agree

In brief: Less than one week

Typically, hives due to a medication will last for only a few days; two weeks tops.
Medications that stay in the body for a few days could cause longer reactions. Adverse reactions to medications should always been discussed with and shown to the prescribing physician, so that the true cause is identified, and your chart is marked so you aren't given that medication again in the future.

In brief: Less than one week

Typically, hives due to a medication will last for only a few days; two weeks tops.
Medications that stay in the body for a few days could cause longer reactions. Adverse reactions to medications should always been discussed with and shown to the prescribing physician, so that the true cause is identified, and your chart is marked so you aren't given that medication again in the future.
Dr. Gary Steven
Dr. Gary Steven
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Dr. John Ebner
Dermatology

In brief: Depends on half life

Different medications have different half lives.
A half life is the time is takes for 1/2 of the drug to be metabolized and passed out of the body. It usually takes 3 half lives for a drug to be considered out of the body. If you know the half life of the drug, then you can make an educated guess about how long the hives will last. It also depends on your body's own metabolic rate (fast/slow).

In brief: Depends on half life

Different medications have different half lives.
A half life is the time is takes for 1/2 of the drug to be metabolized and passed out of the body. It usually takes 3 half lives for a drug to be considered out of the body. If you know the half life of the drug, then you can make an educated guess about how long the hives will last. It also depends on your body's own metabolic rate (fast/slow).
Dr. John Ebner
Dr. John Ebner
Thank
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