Drug Allergy

What is a drug allergy?

A drug allergy is a bad reaction to a drug that happens when the body’s immune system responds to a drug as if it were a dangerous invader and tries to fight it off. Normally the body’s immune system should not react to a drug as though it were an invader, but some drugs can cause that response in some people.

A drug allergy is NOT the same as a drug side effect. Side effects are unintended or unwanted effects that drugs can cause.

What are symptoms of a drug allergy?

There are different types of drug allergies with their own set of symptoms.

“Immediate” allergy – it starts quickly after a drug is taken (usually within an hour or so). This type of allergy is serious because it can get worse if the medicine is continued. It can turn into a life-threatening whole-body allergic reaction, called anaphylaxis. Symptoms include:

  • Wheezing or trouble breathing
  • Chest tightness or pain
  • Passing out or feeling as if you will pass out
  • Swelling of your face, lips, tongue, or throat
  • Hives
  • Severe stomach ache or vomiting
  • High fever
  • Painful skin or skin blisters

Another type of drug allergy, called a “delayed” allergy, which more common. This type is not very serious and usually causes a rash that begins after a few days of taking a drug.

** Call 911 or contact your physician if you have any of the above symptoms.

Can I be tested for a drug allergy?

If your doctor suspects you have an immediate drug allergy, he or she might send you for allergy skin tests.

If you have a reaction that consists only of a rash (the type that is not serious), your doctor might want to send you to do a “drug challenge test.” For this test, the allergist will have you take a small amount of the drug that caused the rash while he or she observes you.

Call for an Appointment Today!

If asthma or allergies make your life unpleasant, the Allergy and Asthma Center of North Carolina can help you.

Asheboro – 336-629-5770
Greensboro – 
High Point – 
Reidsville –