A dopamine agonist medication that binds with dopamine receptors in the brain, simulating the neurotransmitter actions of dopamine. Because ropinirole (Requip) is selective for D2 receptors, its use minimizes some of the undesired side effects such as nausea that occur with ergot-derived dopamine agonists such as bromocriptine (Parlodel) or pergolide (Permax) that bind unselec-tively. it is even slightly more selective than pramipexole (Mirapex) and may carry a bit lower risk of daytime somnolence. Ropinerole is less potent and shorter lived in the bloodstream than the other two commonly used agonists in the United States (pergolide and pramipexole), but it joins pramipexole in showing some evidence that it may be neuroprotective, delaying the progression of dopaminergic neuronal loss in Parkinson’s disease. Ropinirole is sometimes effective as monotherapy in early Parkinson’s and can postpone the need for Levodopa therapy for up to three years. Ropinirole is one of the adjunct therapies used in late Parkinson’s disease, when it extends the availability of dopamine and can allow the lev-odopa dosage to be reduced.
Ropinirole also is sometimes taken as an open-label drug to relieve restless leg syndrome (RLs), a condition in which the legs feel as if they must move. RLS is a common cause of sleep disturbances in people with Parkinson’s but also afflicts people who do not have the disease. Headache, dizziness, and drowsiness are ropini-role’s primary potential side effects.
