This medication is used as a sedative and an anticonvulsant (for treatment of fits).
A person using this may feel drowsiness, ataxia, allergic skin reactions, paradoxical excitement (causes excitement instead of drowsiness), irritability, hyperactivity and confusion, megaloblastic anemia (a type of anemia). Restlessness and confusion in elderly. Hyperkinesia (excessive restlessness) in children. Tolerance and dependence. Lethargy, nystagmus (uncontrolled movement of the eye), respiratory depression, hallucinations, memory and cognitive impairment (person has difficulty remembering), behavioral disturbances, depression.
This medication is contraindicated in patients with severe respiratory depression (fluid build-up in lungs), porphyria (blood disorders). Severe renal (kidney) or hepatic(liver) impairment.