Pramipexole

Pramipexole is a non-ergot dopamine agonist with high selectivity for the D3 dopamine receptor subfamily.

It is licensed for the treatment of the signs and symptoms of idiopathic Parkinson's disease, either as monotherapy in early disease or as an adjunct to levodopa in more advanced stages.

It is also approved for the treatment of moderate to severe restless legs syndrome (RLS).

In Parkinson's disease, pramipexole directly stimulates dopamine receptors in the striatum, compensating for the progressive loss of dopaminergic neurones.

Its preferential D3 agonism may contribute to beneficial effects on mood and motivation in addition to motor symptom control.

As an adjunct to levodopa, pramipexole allows dose reduction of levodopa and may reduce motor fluctuations and off-time in patients with advanced disease.

For restless legs syndrome, pramipexole is taken in a lower dose range and provides effective relief from the uncomfortable urge to move the legs that characterises this condition.

It is usually taken two to three hours before bedtime.

Take with or without food, swallowed whole with water. For Parkinson's disease, doses are taken three times daily at regular intervals.

For restless legs syndrome, take once daily two to three hours before bedtime. Dose increases should be gradual, as directed by your specialist.

Do not stop pramipexole abruptly, as this may cause neuroleptic malignant-like syndrome or dopamine agonist withdrawal syndrome.

If you miss a dose, take it when you remember and adjust subsequent doses accordingly.

Parkinson's disease: start at 0.088 mg (expressed as base) three times daily for the first week, increasing gradually every five to seven days through 0.18 mg, 0.35 mg, to a maximum of 1.

1 mg three times daily (3.3 mg/day). Restless legs syndrome: start at 0.088 mg once daily, increasing every four to seven days to 0.18 mg, then to a maximum of 0.54 mg if needed.

Dose reduction is required in renal impairment (creatinine clearance below 50 mL/min).

Very common: nausea (especially during dose escalation), dizziness, drowsiness, dyskinesia (when used with levodopa).

Common: insomnia, hallucinations (particularly in elderly patients), confusion, constipation, peripheral oedema, postural hypotension, headache, fatigue.

Uncommon but important: impulse control disorders including pathological gambling, compulsive eating, hypersexuality, and compulsive shopping (patients and carers should be warned).

Rare: sudden onset of sleep without warning, which has implications for driving safety.

Warn patients and their families about the risk of impulse control disorders, which may develop insidiously and can have devastating personal and financial consequences.

Ask about gambling, spending, and sexual behaviour at each review. Somnolence and sudden sleep episodes have been reported; advise patients not to drive or operate machinery if affected.

Reduce dose gradually when discontinuing. Use with caution in severe cardiovascular disease, as postural hypotension may occur, particularly during initial dose escalation.

Hallucinations are more common in elderly patients and at higher doses.

Contraindicated in known hypersensitivity to pramipexole or any excipient. No absolute contraindications related to organ function, but significant dose adjustment is required in renal impairment.

Use with extreme caution in patients with pre-existing psychotic disorders.