| Management |
Pharmacologic response and plasma lamotrigine levels should be monitored more closely whenever estrogen- and/or progestin-containing drugs are added to or withdrawn from therapy, and the lamotrigine dosage adjusted as necessary. The manufacturer's labeling should be consulted for detailed dosage recommendations. Patients should be advised to contact their physician if they experience loss of seizure control or symptoms of lamotrigine toxicity such as ataxia, nystagmus, increased seizures, irregular heartbeat, and changes in mental status. In patients receiving oral contraceptives, gradual transient increases in lamotrigine levels will occur during the pill-free week for women not also taking an enzyme-inducing drug (e.g., carbamazepine, phenytoin, phenobarbital, primidone, rifampin). The increase in lamotrigine levels will be greater if the dose of lamotrigine is increased in the few days before or during the pill-free week. Although diminished contraceptive efficacy has not been reported, the possibility should be considered. Patients should be instructed to promptly report changes in their menstrual pattern. |
