Anti-seizures, also known as anticonvulsants are a class of medications used to manage seizure disorders like epilepsy. These drugs are known to fatal adverse reactions like allergies or anaphylaxis when taken unknowingly by a sensitized person.

Mechanism of the allergic reaction

Just about anything can cause allergies—dust, food, pollens, even the drugs that we thought that could save our lives. Without proper knowledge, substances that are normally harmless could provoke systemic reactions that could threaten our body’s integrity.

Before a person becomes allergic to anti-seizure medications, an initial encounter is necessary. During the first exposure, allergens present in the medicine are assumed by the person’s immune system to be detrimental to the body. Subsequently, antibodies known as Immunoglobulin E (IgE) are produced to combat these allergens on succeeding exposures. This process is called sensitization. Common anticonvulsants that cause allergic reactions are carbamazepine (Tegretol) and dilantin (Phenytoin). Reactions generally occur after the next dose. To determine if it’s an allergic reaction, watch out for the following symptoms:

• hives
• swelling of the face, tongue, lips, throat
• difficulty of breathing
• wheezing
• nausea and vomiting
• light headedness

When drugs are introduced systemically or directly to the bloodstream, they could cause a fatal allergic reaction called anaphylaxis. Likewise, any individual who is extremely allergic could suffer anaphylaxis even with a simple skin contact with the offender.

What your Doctor can do for you

If you have a history of allergic reactions with anti-seizure medications, see your doctor, preferably an allergist. He will diagnose your case by assessing your symptoms and clinical history. To help determine whether the drug is causing the allergic reaction, skin tests may be performed.
Allergies are usually managed by their symptoms. Antihistamines like Diphenhydramine can do most of the job, but in severe reactions, epinephrine may be necessary along with other supportive measures. The patient will be required to follow a different treatment regimen consisting of alternative medications.

What you can do

Consider all allergies as an emergency situation as there is a possibility that they may progress into more severe reactions. For any drug allergies, it is very crucial for a sensitized individual to avoid the causative agent at all costs. You may be required to wear a Medic Alert bracelet to warn health professionals of your condition.