What side effects are observed in the treatment of Parkinson’s disease?

Side effects in Parkinson’s disease include:

• Complications of long-term levodopa therapy – dose-wearing-off phenomenon (uneven drug action) and drug-induced dyskinesias
• Hallucinations and delusions (delusional disorders)
• Impulse control disorders

It’s important to remember that some things that initially seem like symptoms of Parkinson’s disease may actually be side effects of medication. Most often, this involves a group of dopamine receptor agonists (piribedil/pronorane, pramipexole/mirapex, ropinirole/requip modutab/sindranol, rotigotine/neupro). Their effectiveness has been proven in numerous studies, and they truly help patients control parkinsonism symptoms. Nevertheless, let’s list their main side effects:

Heart problems are observed with the use of “old” agonists (ergoline) – bromocriptine, pergolide, and cabergoline. This is why these drugs are no longer recommended or used. Unlike the “new” (non-ergoline) ones mentioned above, which are not associated with the risk of heart damage.

Drowsiness, dizziness, and fainting – often observed at the very beginning of taking agonists. Most often, this side effect decreases or disappears upon reaching a stable dose. However, the opposite can also occur – sudden sleep episodes while taking DRAs. This can be a very dangerous condition (for example, when driving), so it’s important to inform your doctor.

Impulse control disorders – the development of uncontrollable and compulsive desires. This behavior may include gambling addiction, shopaholism, excessive increase in libido and sex addiction, overeating/bulimia . This can have a huge impact on the lives of the patients themselves and those around them. Not everyone who takes antiparkinsonian medications will experience such disorders, so these side effects should not scare or deter from taking the medications, as symptoms can be controlled if identified in time.

Hallucinations and Delusions – can have a huge impact on the lives of patients and their relatives. A hallucination is a condition where the patient sees, hears, or feels things that are not present in reality. Delusions (delusional disorders) are unusual thoughts or beliefs not based on reality (e.g., belief in poisoning attempts by neighbors, unfounded certainty of a spouse’s infidelity, belief in attempts to steal). These symptoms can occur with any antiparkinsonian medication but are most often observed with ADRs, especially in the later stages of Parkinson’s disease.

Other Side Effects:
• Nausea
• Worsening or onset of constipation
• Lowering of blood pressure (hypotension)
• Headaches
• Anxiety and depression
If you experience unpleasant or worrying symptoms, it is not necessary to immediately stop the medication on your own. You should inform your doctor as soon as possible for further therapy adjustment.
Wishing you health! Neurologist specializing in Parkinson’s disease at the V.S. Buzaev International Medical Centre, PhD, Gulnara Nailevna Akhmadeeva .