From the Guidelines
Parkinson's disease is primarily treated with levodopa, often combined with carbidopa, as the most effective treatment, despite potential side effects such as nausea, dyskinesia, and wearing-off effects over time. The treatment of Parkinson's disease involves several medication classes that target dopamine deficiency in the brain.
Medication Classes and Side Effects
- Levodopa, often combined with carbidopa (Sinemet), is the most effective treatment, converting to dopamine in the brain to improve movement symptoms, but it may cause nausea, dyskinesia (involuntary movements), and wearing-off effects over time 1.
- Dopamine agonists like ropinirole (Requip) and pramipexole (Mirapex) directly stimulate dopamine receptors but can cause impulse control disorders, hallucinations, and sleepiness 1.
- MAO-B inhibitors such as selegiline (Eldepryl) and rasagiline (Azilect) block dopamine breakdown, extending its effects, with potential side effects including insomnia and high blood pressure with certain foods.
- COMT inhibitors like entacapone (Comtan) prolong levodopa's action but may cause diarrhea and urine discoloration.
- Anticholinergics such as trihexyphenidyl help control tremor but often cause confusion, dry mouth, and urinary retention, especially in older patients.
- Amantadine can reduce dyskinesia but may cause ankle swelling, skin mottling, and hallucinations.
Treatment Approach
Treatment typically begins with milder medications in early disease, adding levodopa when symptoms worsen, with medication adjustments needed throughout the disease course to balance symptom control against side effects.
Recent Guidelines
Recent guidelines suggest the use of pramipexole for the treatment of isolated REM sleep behavior disorder (RBD) in adults, despite the potential for adverse events such as next-day hangover, gastrointestinal symptoms, and negative impulsive behavior 1.
From the FDA Drug Label
There have been reports of patients experiencing intense urges to gamble, increased sexual urges, and other intense urges, and the inability to control these urges while taking one or more of the medications that increase central dopaminergic tone and that are generally used for the treatment of Parkinson's disease, including carbidopa and levodopa tablets Case reports suggest that patients can experience intense urges to gamble, increased sexual urges, intense urges to spend money, binge eating, and/or other intense urges, and the inability to control these urges while taking one or more of the medications, including rasagiline tablets, that increase central dopaminergic tone and that are generally used for the treatment of Parkinson’s disease.
The different medications used to treat Parkinson’s disease include:
- Carbidopa and Levodopa: used to treat Parkinson's disease, but may cause side effects such as intense urges to gamble, increased sexual urges, and other intense urges.
- Rasagiline: used as an adjunct to levodopa, may cause dyskinesia or potentiate dopaminergic side effects and exacerbate pre-existing dyskinesia, and may also cause hallucinations, psychotic-like behavior, and impulse control/compulsive behaviors.
Side effects of these medications may include:
- Intense urges to gamble, increased sexual urges, and other intense urges
- Dyskinesia
- Hallucinations
- Psychotic-like behavior
- Impulse control/compulsive behaviors
- Hypotension/orthostatic hypotension
- Withdrawal-emergent hyperpyrexia and confusion 2 3
From the Research
Medications Used to Treat Parkinson's Disease
- Levodopa, a dopamine precursor, is an effective and well-tolerated dopamine replacement agent used to treat Parkinson's disease (PD) 4
- Dopamine agonists, such as pramipexole, can be used alone before the introduction of levodopa or as an adjunct to levodopa 5, 6
- COMT inhibitors, such as entacapone, can be used to improve the bioavailability of levodopa 4, 7
- MAO-B inhibitors can be used to reduce motor fluctuations in patients with advanced disease 5
- Amantadine may have mild symptomatic benefit and can decrease levodopa-induced dyskinesias 5
- Anticholinergics can be used to control tremor and drooling, but are rarely used due to their adverse effects 5
- Apomorphine can be used as a rescue medication for patients with 'off' episodes 5
Potential Side Effects of Parkinson's Disease Medications
- Levodopa: dyskinesia, hypotonia, gastrointestinal and psychotic symptoms 4, 8
- Dopamine agonists: nausea, dizziness, somnolence, and hallucinations 6
- COMT inhibitors: diarrhea, urine discoloration, and abdominal pain 7
- MAO-B inhibitors: nausea, dizziness, and insomnia 5
- Amantadine: nausea, dizziness, and insomnia 5
- Anticholinergics: dry mouth, constipation, and blurred vision 5
- Apomorphine: nausea, dizziness, and somnolence 5