As this occurs, the margin between an intoxicating dosage
and fatal dosage becomes smaller. Symptoms of acute
intoxication with phenobarbital include unsteady gait, slurred speech, and sustained nystagmus. Mental signs of chronic intoxication include confusion, poor judgment, irritability, insomnia, and somatic complaints . Please consult a neurologist and discuss this with him . If the drug is discontinued after some time , you need not worry . Hope this helps you . Take care and regards !