Antimuscarinic drugs used to treat extrapyramidal side-effects (Formulary)

Antimuscarinic drugs reduce the symptoms of drug-induced Parkinsonism, although tardive dyskinesia is not improved and may be worsened. They do not improve akathisia unless associated with stiffness. Assess the need for antimuscarinic drugs after 3 months of treatment. These drugs have the potential for misuse and careful review of some patients’ motivation in asking for them is required. Antimuscarinic drugs are known to have an effect on cognition, particularly in the elderly.

PROCYCLIDINE

Important: Therapy notes

Important: Formulation and dosage details

Formulation:

Tablets 5mg

Dosage:

By mouth, 2·5mg 3 times daily, increased gradually if necessary; usual maximum 30mg daily. Older people, preferably lower end of range. When stopping reduce stepwise to the minimum effective dose.

Important: Formulation and dosage details

Formulation:

Syrup 2·5mg/5mL

Dosage:

By mouth, 2·5mg 3 times daily, increased gradually if necessary; usual maximum 30mg daily. Older people, preferably lower end of range. When stopping reduce stepwise to the minimum effective dose.

Important: Formulation and dosage details

Formulation:

Solution for injection 10mg/2mL

Dosage:

Acute dystonia, by intramuscular or intravenous injection, 5 to 10mg (occasionally more than 10mg), usually effective in 5 to 10 minutes but may need 30 minutes for relief. Older people, preferably lower end of range.

Editorial Information

Document Id: F103