Allergic Reactions and Chemotherapy

Includes: hypersensitivity, anaphylaxis, drug reaction

What is a chemotherapy or immunotherapy related allergic/hypersensitivity reaction?

An allergic reaction, also referred to as a hypersensitivity reaction, is an overactive or misdirected immune response that results in local tissue injury or changes throughout the body in response to a foreign substance. These reactions can be caused by many factors, including chemotherapy, immunotherapy, biologic agents, other medications, and contrast dye for imaging tests.

Allergic (hypersensitivity) reactions can vary from mild to severe. Symptoms include hives, itching, rash, flushing or redness.

Anaphylaxis is a severe allergic reaction, which can cause shock, low blood pressure, and occasionally death. When chemotherapy medications are known to be common allergic reaction producers, pre-medications are administered to prevent or lessen a possible reaction. If a drug has caused a severe allergic reaction in the past it is unlikely to be used in the future. It is important to report any previous allergic reactions to drugs to your health care professional.

Hypersensitivity allergic reactions have been reported with most chemotherapy drugs, although they are generally infrequent. They occur more commonly with L-asparaginase, paclitaxel, docetaxel, teniposide, procarbazine, and cytarabine. CT contrast dye is also a common cause of allergic reactions.

Common symptoms of this type of reaction are:

• Hives (urticaria): raised, itchy, red blotches or wheals which may be pale in the center and red around the outside. This usually occurs within 36 hours of drug exposure. The lesions rarely last for more than 24 hours
• Swelling or angioedema: a vascular reaction resulting in an increased ability for fluid in the cells to "leak" into the layers of the skin causing swelling. The tongue, lips, or eyelids are generally affected. Swelling of the airways can result in difficulty breathing, closing off of the airway and death. If swelling occurs with any sign of breathing difficulty seek help immediately.
• Itching (pruritis)
• Flushing: a temporary redness of the face and neck caused by dilation of the blood capillaries.
• Maculopapular rash is the most common type of drug-induced allergic skin reactions. It is described as flat reddened rash and may involve small raised bumps.

Symptom Management:

Things you can do to minimize the effects of chemotherapy-induced allergic reactions:

• Notify your healthcare professional of any allergies you may have, including food and drugs. Also let your healthcare professional know if you have had an allergic reaction to any. If you are unsure if it was an allergic reaction or a side effect of the drug it is better to bring it up for discussion. Medication may have to be given before the drug is given again, or a different drug may have to be substituted.
• Take prescribed pre-medications prior to chemotherapy as directed. If you forget, let your healthcare professional know.
• If you develop a rash that is not causing you discomfort make sure your health care professional is aware of the rash so it can be evaluated. Not all rashes require treatment.

Drugs your doctor may prescribe or recommend to minimize the effects of chemotherapy-induced allergic reactions:

If the allergic reaction is severe the offending drug will be discontinued. It may be continued with pre-medications or medication to help relieve symptoms.

General drug classes used in treatment of chemotherapy-based allergic reactions include:

• Antihistamines: These drugs block histamine receptors. These may include diphenhydramine (Benadryl®), zyrtec, allegra, claritin, hydroxyzine, and cyproheptadine.
• Corticosteroids: Steroids work by decreasing inflammation and swelling. People may benefit from steroids, either inhaled, by pill form, or in the vein (IV).
• Dexamethasone and prednisone are common oral steroids used to decrease inflammation.
• Bronchodilators: These drugs work by opening (or dilating) the lung passages, and offering relief of symptoms, including shortness of breath.
• Albuterol is the most common bronchodilator used (also known as a “rescue inhaler”).

If you feel you are having allergic reactions brought on by chemotherapy treatments, the following guidelines suggest when to notify your doctor or health care provider:

Seek emergency help immediately and notify your health care provider, if you experience the following symptoms:

• Shortness of breath, wheezing, difficulty breathing, closing up of the throat, swelling of facial features, hives (possible allergic reaction).

Contact your health care provider within 24 hours of noticing any of the following allergic reactions so the following can be evaluated:

• Skin rash
• Itching
• Hives

Note: We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website is meant to be helpful and educational, but is not a substitute for medical advice.