A syndrome characterized by tremor, rigidity, bradykinesia (slow movement) and postural disturbances, due to primary degeneration or damage to particular areas of the brain (basal ganglia).
Causes
Primary Parkinsonism:
- Cause is unknown
Secondary Parkinsonism:
- Infections e.g. sleeping sickness, syphilis
- Poisoning e.g. manganese, carbon monoxide
- Drugs e.g. chlorpromazine, haloperidol
- Vascular disorders, intracranial tumour, trauma
Clinical features
- Non intentional tremor
- Muscle rigidity
- Slowness of voluntary movement
- Walking with short quick steps (shuffling gait)
- Vacant facial expression (mask face)
- Excessive salivation
- Urinary incontinence (sometimes occurs)
- Variable cognitive impairment
Differential diagnosis
- Essential tremor (isolated intentional tremor, benign)
- Thyrotoxicosis
- Dementia, depression
Investigations
- Good history and clinical examination
Management
- Levodopa-carbidopa 100/25 mg
- Start with 1 tablet every 8 hours (specialist only management)
Only for drug-induced parkinsonism
- Benzhexol 2-15 mg daily in 1-3 divided doses
- Initially: 1 mg/day; increase by 2 mg increments at intervals of 3 to 5 days
- Usual dose: 6 to 10 mg/day in 3 to 4 divided doses; doses of 12 to 15 mg/day may be required
Caution
- Benzhexol side effects: dry mouth, constipation, palpitations, urinary retenton, confusion and agitation
(especially in the elderly) - Do not give benzhexol routinely to patients on antipsychotic medicines in the absence of parkinsonlike
side effects - Use lower doses in elderly