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Drug interactions between Topamax and zonisamide

Results for the following 2 drugs:
Topamax (topiramate)

Interactions between your drugs


topiramate ↔ zonisamide

Applies to:Topamax (topiramate) and zonisamide

Talk to your doctor before using topiramate together with zonisamide. Both of these medications can cause metabolic acidosis, a condition associated with elevated levels of acid in the blood, and combining them may increase the risk as well as severity of the condition. Patients with metabolic acidosis may have no symptoms at all, or they may experience tiredness, loss of appetite, irregular heartbeat, trouble thinking clearly, and rapid breathing. If left untreated, metabolic acidosis can also lead to kidney stones, brittle or soft bones (osteomalacia, osteopenia, osteoporosis), reduced growth rates in children, and harm to the unborn baby during pregnancy. Patients receiving these medications, whether together or alone, generally require a blood test to measure the level of acid in the blood before and during treatment. Another potential issue with combining these medications is the risk of heat-related disorders. Decreased sweating and increased body temperature have been reported, particularly in children. Heat stroke may occur during vigorous exercise or prolonged exposure to warm or hot weather. Increased fluid intake is recommended during treatment to help prevent heat-related problems and kidney stones. Contact your doctor immediately if you develop signs or symptoms of kidney stones such as sudden back pain, abdominal pain and blood in the urine, of if you have decreased sweating or a fever. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

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Drug Interaction Classification

The classifications below are a guideline only. The relevance of a particular drug interaction to a specific patient is difficult to determine using this tool alone given the large number of variables that may apply.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No information available.

Do not stop taking any medications without consulting your healthcare provider.

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