List of products in the National Drug Code with proprietary name . Rasagiline is used alone or with other medications (such as levodopa/carbidopa) to treat symptoms of Parkinson's disease. It can help improve symptoms such as shakiness, stiffness, and difficulty moving. It can also help reduce the amount of "off" time (periods of slow movement or stiffness). Rasagiline belongs to a class of drugs known as MAO inhibitors. It works by increasing the levels of certain natural substances in the brain (such as dopamine, norepinephrine, serotonin). Parkinson's disease is thought to be caused by too little dopamine in the brain.