Parkinson's Disease Health Center

Medicines are the most common treatment for Parkinson's disease. The goal is to correct the shortage of the brain chemical (neurotransmitter) dopamine, which causes the symptoms of Parkinson's disease. Treatment with drugs is usually started when symptoms become disabling or disrupt a person's daily activities.

Drugs for Parkinson's disease are prescribed with specific instructions about when to take them. It is important to follow your doctor's instructions concerning how and when to take your drugs so that they will be effective and safe. Increasing, decreasing, or stopping the medicines you are taking may cause big changes in your symptoms and can be dangerous. Even if a medicine doesn't seem to be working, when you stop taking it, your symptoms of Parkinson's disease may be worse.

Treatments may differ based on a person's symptoms and age and how the person responds to a certain drug. Drugs often improve symptoms, but they also may cause side effects. It may take some time to find the best combination of drugs for a particular person.

Currently, levodopa is thought to be the most effective drug for controlling symptoms of Parkinson's disease and for many years was the preferred drug for treating newly diagnosed people.⁵ But because long-term use of levodopa at high dosages often leads to motor complications that can be difficult to manage, sometimes doctors use dopamine agonists (such as pramipexole and ropinirole) to treat people during the early stages of Parkinson's disease. Using these drugs in the early stages of the disease may allow treatment with levodopa to be delayed. But dopamine agonists have more side effects and don't control symptoms as well as levodopa. And in the long term, the same amount of people have motor complications no matter what medicine is used first.¹

The decision about whether it is better to use levodopa or a dopamine agonist as the first treatment has not been fully resolved. The choice will most likely be different for each person. It is important to work with your doctor to find the medicines that work the best for you.

Medication Choices

Several drugs may be used to treat Parkinson's disease at different stages of the disease.

In general, treatment of early Parkinson's starts with one or more of these medicines:

• Levodopa and carbidopa
• Dopamine agonists (for example, pramipexole or ropinirole)
• COMT inhibitors (entacapone, tolcapone)
• MAO-B inhibitors (rasagiline, selegiline)
• Amantadine
• Anticholinergic agents (for example, benztropine or trihexyphenidyl)

Apomorphine. This medicine is a fast-acting dopamine agonist used for treating occasional episodes of immobility associated with Parkinson's disease. Apomorphine can be injected under the skin when muscles become "stuck" or "frozen" and you are unable to rise from a chair or perform daily activities.

What To Think About

Early in the disease, it might be helpful to take pills with food to help with nausea, which may be caused by some medicines taken for Parkinson's disease. Later in the disease, taking the medicines at least one hour before meals (and at least two hours after meals) may help them work best. Some medicines for Parkinson's disease don't work as well if you take them at the same time you eat food with protein in it, such as meat or cheese. The protein can block the medicine and keep it from working as well as it should.