For adults, Sabril is usually started at 500 milligrams (mg) twice daily. The dosage can be increased to 1000 mg twice a day after two weeks, then 1500 mg twice a day two weeks later. Dosage usually would be continued at 1500 mg twice a day (3000 mg per day total). For people who are particularly prone to medication side effects, the initiation may start more slowly. On the other hand, some patients with an urgent need to control seizures quickly might increase dosage faster than usual. You should plan the medication schedule with your doctor.