Medications for Parkinson’s Disease

Though there is no absolute cure for Parkinson’s disease (PD), certain medications can pause its progression or ease certain symptoms. With different patients experiencing different severity level and symptoms, same treatment cannot be prescribed to every patient suffering from the condition.  

A number of medications are available for easing various Parkinson’s symptoms. These medications target minimizing tremors and slowness of the movement along with the associated symptoms of sleep disorder, low blood pressure, and anxiety. Foot swelling and hallucinations are among most common side effects of various medication classes. Parkinson’s medications can be categories into three groups – medicines that increase the dopamine levels in the brain, medications that affect other neurotransmitters to relieve some of the symptoms and drugs that help patients control non-motor symptoms. Commonly prescribed Parkinson’s medications include:

1. Levodopa-Carbidopa

Levodopa is the most prescribed medication for people suffering from Parkinson’s. The drug intake gets converted into Dopamine and stored in nerve cells to replace depleted dopamine ( a neurotransmitter that helps the brain to regulate body movement). However, when consumed alone, it can produce nausea and vomiting. To prevent such side effects, Carbidopa is prescribed with Levodopa. The combination reduces the tremors and associated symptoms during the early stages of Parkinson’s.

2. Dopamine Agonists

Used in the early stages of the disease, Dopamine Agonists mimic the role of dopamine. However, Dopamine Agonists are observed to be less effective than Levodopa in controlling muscle rigidity and Bradykinesia. Excessive daytime sleepiness, hallucinations, confusion and swelling of the ankles are commonly reported side effects of this medication.

3. MAO-B Inhibitors

MAO-B inhibitors help to block the dopamine’s breakdown in the brain so that more dopamine is available to reduce some of the motor symptoms of the disease. They decrease the normal activity of Monoamine Oxidase, an enzyme responsible for breaking down the dopamine. The most common side effects of MAO-B inhibitors include mild nausea, light-headedness, constipation, dry mouth, hallucinations (particularly in the elderly patients) and confusion.

4. COMT Inhibitors

Catechol-O-Methyl Transferase, popularly known as COMT, blocks an enzyme that breaks down Levodopa – a key drug used to treat Parkinson’s. It is a complementary medicine that is taken alongside Levodopa or the combination of Levodopa and Carbidopa.  The most common side effect of the drug is Dyskinesias (abnormality of voluntary movement).

5. Other Drugs

5a. Anticholinergic

The oldest class of medications to treat Parkinson’s, Anticholinergics are more helpful for treating tremor-predominant younger patients. Common side effects of the medication include confusion, hallucinations, decreased short-term memory, dry mouth, blurry vision and urinary retention.

5b. Amantadine

Initially discovered as an antiviral medication for influenza, Amantadine is prescribed in combination with Levodopa to treat Dyskinesias, usually for mild relief in early stages of the disease.