wellbutrin-sr and Amantadine Interactions

Interactions between wellbutrin-sr(buPROPion) and Amantadine (amantadine)

amantadine and buPROPion (Major Drug-Drug)

MONITOR CLOSELY: The use of bupropion is associated with a dose-related risk of seizures. The estimated incidence of seizures is approximately 0.1% at dosages up to 300 mg/day and 0.4% at dosages between 300 to 450 mg/day, but increases almost tenfold between 450 mg and 600 mg/day. The risk may also be increased during coadministration of bupropion with other potentially epileptogenic agents such as amantadine.

MONITOR CLOSELY: According to the product labeling for bupropion, limited clinical data suggest a higher incidence of adverse experiences in patients receiving bupropion concurrently with either levodopa or amantadine. Neither the mechanism of interaction nor specific adverse effects are cited. According to a published case report, neurotoxic effects including ataxia, dizziness, vertigo, agitation, tremors, and gait abnormalities occurred in 3 elderly patients following addition of amantadine to bupropion therapy. The symptoms resolved within 72 hours after discontinuation of both drugs. The authors theorize that additive central dopaminergic effects of the drugs may have caused the apparent interaction.

MANAGEMENT: Extreme caution is advised if bupropion is administered with amantadine, particularly in the elderly and in patients with a history of seizures or other risk factors for seizures (e.g., head trauma; brain tumor; severe hepatic cirrhosis; metabolic disorders; CNS infections; excessive use of alcohol or sedatives; addiction to opiates, cocaine, or stimulants; diabetes treated with oral hypoglycemic agents or insulin). The manufacturer recommends a lower initial dosage of bupropion and gradual dosage increments in patients receiving the drugs concurrently. The total dose of bupropion should generally not exceed 450 mg/day (or 150 mg every other day in patients with severe hepatic cirrhosis). Bupropion should be discontinued and not restarted in patients who experience a seizure during treatment.