Adverse effect

Onset

Clinical features

Parkinsonism

Days to weeks

Tremor, shuffling gait, drooling, stooped posture

Akathisia

Hours to days

Agitation, inner restlessness, pacing, fidgeting

Acute dystonia

Hours to days

Torticollis, oculogyric crisis, laryngospasm

Tardive dyskinesia

Months to years

Choreoathetoid movements of tongue, extremities, and trunk; grimacing; lip smacking; chewing