Overview
Ropinirole is a dopamine agonist used in the treatment of Parkinson’s disease and Restless Legs Syndrome (RLS). It acts directly on dopamine receptors in the brain, mimicking the effects of dopamine to help improve motor function and reduce the urge to move the legs.

Mechanism of Action
It is a non-ergoline dopamine agonist with high affinity for D2 and D3 dopamine receptors. In Parkinson’s disease, it stimulates these receptors in the striatum, compensating for the depleted dopamine levels and improving motor symptoms. In RLS, its exact mechanism is unknown but is thought to involve the dopaminergic system.

Dosage and Administration
For Parkinson’s disease, the dose is titrated gradually over several weeks to minimize side effects, starting typically at 0.25 mg three times daily. Extended-release formulations are also available for once-daily dosing. For RLS, it is taken once daily, 1 to 3 hours before bedtime.

Side Effects
Common side effects include nausea, dizziness, somnolence (drowsiness), and peripheral edema. It can cause sudden sleep onset episodes, which can be dangerous while driving. Impulse control disorders (such as pathological gambling or hypersexuality) have also been reported with dopamine agonists.

Contraindications
It is contraindicated in patients with a known hypersensitivity to ropinirole. Caution is advised in patients with severe cardiovascular disease or hepatic impairment.

Pregnancy and Lactation
It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. It may inhibit prolactin secretion and thus interfere with lactation; it is not recommended for nursing mothers.