From the Research
Dopamine agonists are more likely to cause central nervous system (CNS) side effects, such as hallucinations, than levodopa in a 55-year-old woman newly diagnosed with Parkinson's disease. According to a meta-analysis published in The Cochrane database of systematic reviews 1, dopamine agonists were found to increase the risk of various 'non-motor' side-effects, including hallucinations, compared to levodopa-treated participants. This is because dopamine agonists stimulate dopamine receptors throughout the brain, not just in the movement-related pathways affected by Parkinson's disease.
Some key points to consider when treating a newly diagnosed 55-year-old woman with Parkinson's disease include:
- Dopamine agonists, such as pramipexole (Mirapex), ropinirole (Requip), and rotigotine (Neupro), can cause CNS side effects, including hallucinations, confusion, impulse control disorders, excessive daytime sleepiness, and sleep attacks.
- Levodopa (often combined with carbidopa as Sinemet) tends to cause fewer CNS side effects initially, particularly in younger patients, making it generally better tolerated.
- However, levodopa is more associated with motor complications like dyskinesias after long-term use.
- When treating a newly diagnosed 55-year-old woman with Parkinson's disease, the clinician should consider starting with levodopa if CNS side effects are a concern, especially if the patient has any cognitive impairment or history of psychiatric issues.
- The typical starting dose would be carbidopa-levodopa 25/100 mg three times daily, adjusted based on symptom control and tolerability.
It's also worth noting that other studies have found similar results, with dopamine agonists being associated with a higher risk of CNS side effects compared to levodopa 2, 3, 4, 5. However, the most recent and highest quality study, published in 2008 1, provides the strongest evidence for this recommendation.