Drug allergy is immunologically mediated reaction to certain medicines which occurs within minutes to hours after taking that medicine. Even a small amount of drug is sufficient to trigger allergy symptoms. In some individuals, a medicine allergy can cause severe allergy symptoms or even a life-threatening reaction called anaphylaxis.

The most common medication causing allergy include:

Antibiotics, such as penicillin, sulfonamides.
Aspirin and non-steroidal anti-inflammatory medications, such as Ibuprofen
Few Anticonvulsants
Monoclonal antibody therapy
Chemotherapy drugs

Symptoms of Drug Allergy

Signs and symptoms of a serious allergy often occur within minutes to hour after taking a drug. Other reactions, particularly rashes, can occur hours, days or weeks later.

Most common symptoms include:

Skin rash
Hives
Itching
Fever
Swelling
Shortness of breath
Wheezing
Runny nose
Itchy, watery eyes
Anaphylaxis

Anaphylaxis is the most severe form of allergic reaction which requires urgent attention. If someone has anaphylaxis then he must inject adrenaline/epinephrine autoinjector.

Management of Drug Allergy:

These strategies include:

Management for present allergy symptoms
Treatment that may enable you to take an allergy-causing drug if it’s medically necessary
Avoidance of the drugs causing symptoms

Treating current symptoms

Withdrawal of the drug stopping the drug is the first step in treatment. In many cases, this may be the only intervention necessary.
Antihistamines antihistamine like diphenhydramine that can block immune system chemicals activated during an allergic reaction.
Corticosteroids. Either oral or injected corticosteroids may be used to treat inflammation associated with more-serious reactions.
Treatment of anaphylaxis. Anaphylaxis requires an immediate epinephrine/adrenaline injection as well as hospital care to maintain blood pressure and support breathing.

If your child has an allergy to certain medications, you must follow few steps to ensure your child is safe:

Always notify key people about the child’s allergy. Inform your child care providers, school personnel, parents of your child’s friends and other adults who regularly interact with your child. Tell them that medicine allergy may life-threatening and may require urgent intervention to save the life of the child.
Explain drug allergy symptoms to persons who spend time with the child.
Have a written action plan. This plan should include the appropriate management strategies to care for the child in case of allergy and in an emergency case of anaphylaxis. One copy of the plan must be given to school authority.
Have your child wear a medical alert bracelet or necklace to display that he/she has an allergy to certain medicine.