Parkinson’s disease drugs may cause daytime sleepiness. Some people experience sleep attacks, during which they suddenly feel intensely tired or even fall asleep.
Because modafinil is a stimulant, it can help people feel more awake and alert. Some also experience a heightened sense of focus on the drug, which can help reduce the side effects of Parkinson’s treatments.
Modafinil does not treat other Parkinson’s symptoms, such as tremors, constipation, and neurological issues.