Drug Allergy: Symptoms & Signs

Medically Reviewed on 7/28/2020

A drug allergy is an allergic reaction to a medication or drug of any type, whether it is prescription or non-prescription. Penicillins and sulfa drugs are common examples of drugs that sometimes cause an allergic reaction. In severe cases, life-threatening anaphylactic shock may occur.

Signs and symptoms of a drug allergy are similar to those of other allergic reactions. These can include a

Other associated symptoms and signs can include

More serious reactions may cause

Cause of a drug allergy

An immune response causes a drug allergy.

Other drug allergy symptoms and signs


Allergies can best be described as: See Answer

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Jameson, J. Larry, et al. Harrison's Principles of Internal Medicine, 20th Ed. New York: McGraw-Hill Education, 2018.