For many people with insulin allergies, the allergy goes undetected until they suffer an allergic reaction. The first goal of treatment generally is to relieve the symptoms of a local allergic reaction and to prevent anaphylactic shock if a severe reaction is occurring. Diabetic individuals using insulin should consult their physician to assess their risk of insulin allergy and the appropriate response if such an occurrence is suspected.

Some of the typical approaches to an allergic reaction include administering an antihistamine, which may be given to relieve mild symptoms, such as itching and rash. Antihistamines are a group of drugs that block the effects of histamine, a chemical released during an allergic reaction.

Corticosteroid cream or tablets may be recommended when skin rashes fail to clear up. Corticosteroids are a group of anti-inflammatory and immunosuppressive drugs similar to hormones produced by the body. In patients with asthma-like symptoms, such as wheezing or cough, a bronchodilator may be prescribed. Bronchodilators are a group of drugs used to widen the lungs’ airways (bronchi).

In cases of anaphylaxis, treatment is frequently an injection of epinephrine. Epinephrine constricts the blood vessels, prevents fluid leakage, opens the airways and raises blood pressure. It also quickly relieves the itching and skin flushing that is part of most episodes of anaphylaxis.

Patients with a history of severe reactions may have a prescribed epinephrine injection kit to treat themselves in an emergency. These patients may be advised in advance by their physician to administer their shot while someone else calls for emergency help. Those who do not have access to epinephrine must seek emergency treatment immediately. Epinephrine may then be administered in an emergency room or by emergency personnel.

To diagnose an insulin allergy, a physician will ask patients about their medical history and perform a physical examination.

Symptoms and a history of allergies to medications are usually enough to diagnose an insulin allergy. A physician may order an allergy skin test to determine if any form of insulin can be tolerated. A variety of insulin types can be introduced to the skin. The test is positive if the skin shows a reaction.

When a patient reacts to all types of insulin, a physician may recommend desensitization. Desensitization is the process of reducing or eliminating a patient’s sensitivity to an allergen. This is accomplished over time by injecting the patient with small but increasing amounts of the allergen. Desensitization is a risky procedure and is considered only in cases when there are no alternative medications or therapies available.

The insulin type that triggered the smallest allergic reaction is usually used in the desensitization process. After the first dose is introduced, the patient is asked to wait a specific time period until the next dose. Increasing doses of insulin are given over a period of minutes or hours to days, until the usual therapeutic dose is tolerable. The patient is monitored for some time after each dose to ensure that a significant allergic reaction is not occurring. Allergic reactions can occur at any time, even when the previous doses did not trigger a reaction. Should allergy symptoms appear during the desensitization therapy, allergy medications (e.g., antihistamines, corticosteroids or epinephrine) may be administered to relieve the symptoms.

There is no known way to prevent the development of an insulin allergy. However, patients may be advised by their physician to avoid discontinuing insulin therapy because insulin allergies are more common in patients with a history of interrupted insulin therapy.