Parkinsonism, secondary

G21.0-4/G21.8-9

• Description
• General measures
• Medicine treatment

DESCRIPTION

Secondary parkinsonism is caused by certain medicines (typical and atypical antipsychotics, anti-emetics, anticonvulsants (phenytoin, valproate/ valproic acid) and SSRIs), a different nervous system disorder, or another illness.

GENERAL MEASURES

Primary approach in drug-induced parkinsonism should be to stop the offending medicine if possible.

Refer to psychiatric services for review of antipsychotic treatment in patients requiring treatment for parkinsomism (see section 15.5.2: Schizophrenia spectrum disorders).

MEDICINE TREATMENT

Anticholinergics have a limited role in this setting and should be used with caution.

• Anticholinergic agent, e.g.:
• Orphenadrine, oral, 50 mg 8 hourly, increase gradually according to clinical response.
  • Usual dose: 150–250 mg daily.

LoEIII [67]

Note: Anticholinergic side effects are common and may be exacerbated by antipsychotics.

OR

• Carbidopa/levodopa, 25/100 mg (1 tablet), oral, 8 hourly.

Acute dystonic reaction:

Usually follows administration of dopamine-antagonistic drug, e.g. metoclopramide and phenothiazines.

• Anticholinergic agent, e.g.:
• Biperiden, IM/IV, 2 mg.
  • Repeat as necessary.

OR

• Promethazine, deep IM, 25–50 mg.
  • In the elderly 25 mg.

LoEIII