Drug Interaction Results
Drug interaction results for the following 3 drug(s):
Keppra (levetiracetam)
Tegretol XR (carbamazepine)
Topamax (topiramate)
Interactions between your selected drugs
Moderate Drug-Drug Interaction Tegretol XR (carbamazepine) and Topamax (topiramate) (Moderate Drug-Drug)
ADJUST DOSE: Carbamazepine, when coadministered with topiramate may lead to a 40% decrease in the plasma concentration of topiramate. The mechanism of action appears to be due to increased metabolism of topiramate.
MANAGEMENT: If dosages of topiramate have been adjusted up, reduction or withdrawal of carbamazepine during adjunctive therapy may require a downward dose adjustment of topiramate. No adjustment in carbamazepine dosage is required when topiramate adjunctive therapy is started. Patients should be monitored for seizure control and should be advised to notify their physician if seizure control worsens.
Moderate Drug-Drug Interaction Tegretol XR (carbamazepine) and Keppra (levetiracetam) (Moderate Drug-Drug)
MONITOR: Central nervous system- and/or respiratory-depressant effects may be additively or synergistically increased in patients taking multiple drugs that cause these effects, especially in elderly or debilitated patients.
MANAGEMENT: During concomitant use of these drugs, patients should be monitored for potentially excessive or prolonged CNS and respiratory depression. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.
Other drugs that your selected drugs interact with
• There are 715 other drugs known to interact with Keppra (levetiracetam)
• There are 2270 other drugs known to interact with Tegretol XR (carbamazepine)
• There are 841 other drugs known to interact with Topamax (topiramate)
Interactions between your selected drugs and food
Moderate Drug-Food Interaction Tegretol XR (carbamazepine) (Moderate Drug-Food)
GENERALLY AVOID: In a small, randomized, crossover study, the administration of carbamazepine with grapefruit juice (compared to water) increased plasma drug concentrations by approximately 40%. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits.
MANAGEMENT: Given the drug's narrow therapeutic index, patients receiving carbamazepine therapy should preferably avoid the regular consumption of grapefruits and grapefruit juice to prevent any undue fluctuations in plasma drug levels. Patients should be advised to report signs of carbamazepine toxicity (nausea, visual disturbances, dizziness, or ataxia) to their physicians.