zonisamide

Zonisamide (Zonegran) is a sulfonamide or sulfa medication. Don’t take zonisamide (Zonegran) if you're allergic to sulfa medications (e.g., Bactrim (sulfamethoxazole / trimethoprim), sulfasalazine (Azulfidine)), since you might have a severe allergic reaction. Get medical attention right away or go the emergency room if you notice a skin rash, swelling of the face or throat, or have difficulty breathing while taking zonisamide (Zonegran).

Although rare, zonisamide (Zonegran) can cause life-threatening skin reactions. In most cases, people start out with flu-like symptoms (such as fever, cough, sore throat, and fatigue) that develop into painful rashes and blisters on the body. Let your provider know if you notice any unusual rashes during treatment with zonisamide (Zonegran).

Some people taking zonisamide (Zonegran) have had serious and life-threatening allergic reactions affecting certain organs (such as the heart, kidneys, and liver). Symptoms of such allergic reactions can include fever, rash, severe muscle pain, swelling of the face, and yellowing of the skin or white part of the eyes. Let your provider know right away or get immediate medical attention if you notice any of these symptoms while taking zonisamide (Zonegran).

Zonisamide (Zonegran) treatment can make you less likely to sweat, which can make it harder for you to control your body temperature. This can put you at a higher risk for heat stroke, which can be life-threatening if not treated. The risk of this side effect is higher in younger people who take zonisamide (Zonegran). To prevent overheating, drink plenty of liquids, stay in the shade, and avoid staying in the sun too long if the weather is hot while taking zonisamide (Zonegran).

Some people taking zonisamide (Zonegran) experienced higher than normal pressure in their eyes. This can lead to blurred vision, eye pain, and eye redness. If left untreated, it can also lead to permanent loss of vision. Eye problems might begin within one month of starting treatment with zonisamide (Zonegran). Let your provider know if you start having eye problems while taking this medication.

Zonisamide (Zonegran), like other medications used for seizures, can raise the risk of suicidal thoughts or behavior. Suicidal thoughts can happen as early as one week after starting this medication. If you or a loved one notices your mood worsening or thoughts of hurting yourself after you start taking zonisamide (Zonegran), talk to your provider right away.

Zonisamide (Zonegran) can make it harder for you to concentrate or remember things. It can also cause problems with speech, coordination, mood (new or worsening depression), and make you more sleepy. Be careful driving or doing anything that requires mental alertness while taking zonisamide (Zonegran).

Zonisamide (Zonegran) can raise your risk of getting kidney stones. Kidney stones can cause pain, but also sometimes fever, nausea, and blood in your urine. Usually, the stones pass on their own, but can require treatment at times. Zonisamide (Zonegran) can also affect how well your kidneys work, especially if you take the medication for a long time. If you have blood in your urine, changes in how often you urinate, swollen feet or ankles, excessive tiredness, or muscle cramping, talk to your provider. This could be a sign that zonisamide (Zonegran) is affecting your kidneys.

In some rare cases, zonisamide (Zonegran) can raise the level of acid in your blood (metabolic acidosis). If not treated in time, it can cause kidney stones, or weaken your bones and make them likely to break. Metabolic acidosis can also lead to high levels of ammonia in the blood, which can affect the brain and cause you to become more tired, unable to concentrate, or vomit. Your provider might do regular blood tests to make sure there are no major changes in your blood acid level. If you develop metabolic acidosis during your treatment with zonisamide (Zonegran), your provider might decide that you need to stop taking the medication by slowly lowering the dose. In some cases, you might receive treatment for metabolic acidosis if your provider wants you to continue taking zonisamide (Zonegran). Contact your provider if you experience fast breathing, vomiting, or confusion during treatment, since these can be signs of high blood acid levels.

Talk to your provider before stopping zonisamide (Zonegran). Stopping zonisamide (Zonegran) suddenly can cause your seizures to come back or become worse. Your provider will work with you to lower your dose slowly over time so this doesn't happen.