Ropinirole

Ropinirole is a non-ergot dopamine agonist used primarily in the management of Parkinson's disease and moderate to severe restless legs syndrome (RLS).

In Parkinson's disease, it may be used as monotherapy in early disease or as an adjunct to levodopa in more advanced stages to help manage motor fluctuations and reduce 'off' time.

The drug works by directly stimulating dopamine D2 and D3 receptors in the brain, mimicking the action of dopamine in the basal ganglia.

This compensates for the depletion of endogenous dopamine that characterises Parkinson's disease.

In restless legs syndrome, ropinirole is thought to act on dopaminergic pathways in the central nervous system to reduce the uncomfortable sensations and urge to move the legs that typically worsen during rest or in the evening.

Ropinirole is available as immediate-release tablets for flexible dosing throughout the day and as prolonged-release tablets for convenient once-daily administration.

Dose titration is essential to minimise side effects, and treatment should always be started at a low dose with gradual upward adjustment.

Take ropinirole by mouth as directed by your doctor. Immediate-release tablets are usually taken three times daily, with or without food, though taking with food may reduce nausea.

Prolonged-release tablets are taken once daily and should be swallowed whole without crushing, chewing, or splitting.

For restless legs syndrome, the dose is taken once daily, 1 to 3 hours before bedtime. Do not stop ropinirole suddenly; the dose must be reduced gradually under medical supervision.

For Parkinson's disease: start at 0.25 mg three times daily, increasing weekly by 0.25 mg per dose.

The usual maintenance dose is 3 mg to 9 mg daily in three divided doses, up to a maximum of 24 mg daily. For restless legs syndrome: start at 0.

25 mg once daily 1-3 hours before bedtime, increasing gradually to a maximum of 4 mg daily. Dose adjustments may be required in patients with renal impairment.

Very common (more than 1 in 10): nausea, dizziness, somnolence.

Common (1 in 10 to 1 in 100): vomiting, abdominal pain, constipation, hallucinations (more frequent in elderly patients and with Parkinson's disease), peripheral oedema, postural hypotension, confusion.

Uncommon (1 in 100 to 1 in 1,000): excessive daytime sleepiness with sudden sleep onset, impulse control disorders (pathological gambling, hypersexuality, compulsive spending, binge eating).

Rare (1 in 1,000 to 1 in 10,000): psychotic reactions, hepatic reactions. Patients and carers should be alert to behavioural changes.

Dopamine agonists including ropinirole may cause impulse control disorders. Patients and their carers should be informed about this risk and monitored regularly.

Sudden onset of sleep has been reported, which is particularly relevant for patients who drive or operate machinery.

Ropinirole may cause postural hypotension, especially during dose titration; patients should be advised to rise slowly from sitting or lying positions.

Dose reduction should be gradual, as abrupt withdrawal may precipitate neuroleptic malignant syndrome-like symptoms.

Ropinirole is contraindicated in patients with severe renal impairment (creatinine clearance below 30 ml/min) without dialysis, severe hepatic impairment, and known hypersensitivity to ropinirole or any of the excipients.

Caution is advised in patients with severe cardiovascular disease and a history of psychotic disorders.