Table 4

Doses of common treatments in tardive dyskinesia and tardive dystonia

TrihexyphenidylTetrabenazineClonazepamClozapine
Starting dose1 mg12.5 mg od250 µg od (125 µg od if elderly)12.5 mg od
Increase by1 mg every 4–7 days12.5 mg weekly250 µg weeklyIn conjunction with a psychiatrist
Aim for2–4 mg tds25–50 mg tds0.5–1 mg bd–tds12.5–25 mg bd
Side effectsDry mouth, dry eyes, nausea, confusion, constipation, urinary retentionParkinsonism, depressionSedation, depression, fatigueAgranulocytosis (register patient with clozapine blood monitoring programme through pharmaceutical company), cardiomyopathy, seizures
ContraindicationsAcute closed angle glaucomaSevere depressionAcute closed angle glaucoma, severe liver dysfunctionCardiac disease

  • bd, twice daily; od, once daily; tds, three times daily.