Pramipexole is indicated for:

• Treatment of Parkinson’s disease, either as monotherapy or as adjunct therapy with levodopa combined with a dopa-decarboxylase inhibitor
• Moderate to severe restless legs syndrome (RLS)

The exact mechanism of action of pramipexole in Parkinson’s disease is not fully understood. It is believed to exert its effect by stimulating dopamine receptors in the striatum of the brain, an area involved in controlling multiple neurological functions. Animal studies suggest that pramipexole affects neuronal transmission in the striatum after activation of dopamine receptors. Pramipexole is a non-ergot dopamine agonist with high specificity and strong activity at the D2 receptor family in vitro. It binds selectively to dopamine D2 receptors and shows preference for the D3 receptor subtype over other dopamine receptor subtypes. The clinical significance of this receptor selectivity is not fully known.

The recommended dose of Pramipexole is as follows Parkinson's disease:

• Initial dose: 88 micrograms 3 times daily, dose doubled every 5-7 days if tolerated to 350 micrograms 3 times daily; further increased if necessary by 180 micrograms 3 times daily at weekly intervals
• Maximum dose: 3.3 mg daily in 3 divided doses. During pramipexole dose titration and maintenance Levodopa dose should be reduced.

Restless legs syndrome:

• Initial dose: 88 micrograms once daily 2-3 hours before bedtime, dose doubled every 4-7 days if necessary to 350 micrograms daily.
• Maximum dose: 540 micrograms daily.

Use in children: Pramipexole is not recommended for children below 18 years of age.

Pramipexole is a dopamine agonist that is not significantly metabolized by the cytochrome P450 system, which reduces the likelihood of drug–drug interactions. However, cimetidine and amantadine may decrease its renal clearance. Concomitant use with sedative medicines or alcohol may produce additive central nervous system depressant effects

Pramipexole is contraindicated in patients with known hypersensitivity to pramipexole or to any of the excipients in the formulation.

Common adverse effects include dizziness, dyskinesia, nausea, hypotension, abnormal dreams, confusion, constipation, delusions, hallucinations, headache, hyperkinesia, binge eating, insomnia, libido disorders, peripheral oedema, paranoia, pathological gambling, hypersexuality, abnormal behaviour, somnolence, weight gain, sudden sleep onset, pruritus, rash, and other hypersensitivity reactions.

The effects of pramipexole on pregnancy and lactation in humans have not been established. It should be used during pregnancy only if the potential benefit outweighs the potential risk to the fetus. Pramipexole inhibits prolactin secretion in humans. Its excretion in breast milk has not been studied; therefore, it is not recommended during breastfeeding. If its use is necessary, breastfeeding should be discontinued.

Caution is advised in patients with psychotic disorders. Regular ophthalmologic monitoring is recommended. Care should also be taken in patients with severe cardiovascular disease and renal impairment.

There is limited clinical experience with overdose. Symptoms may include nausea, vomiting, hyperkinesia, hallucinations, agitation, and hypotension. There is no specific antidote. In cases of central nervous system stimulation, a neuroleptic agent may be used. Management includes general supportive measures such as gastric lavage, intravenous fluids, activated charcoal, and ECG monitoring.

Antiparkinson drugs

Store in a cool, dry place. Protect from light.