available over the counter: no

uses: treatment of partial  seizures (seizure involves movement of an isolated portion of the body;  may be used alone or  in conjunction with other anticonvulsant medications

mechanism of action: mechanism unclear

side effects
• common: drowsiness, fatigue, clumsiness, gait abnormalities, visual disturbances
• less common: muscle weakness, insomnia, nervousness, speech difficulties, impaired concentration, acne
• serious: none

concerns: do not stop medication abruptly;  taper, per physician over weeks