Most Commonly Used Medicines for Parkinson’s Disease

Living with Parkinson’s disease can be challenging, not just for the person diagnosed but also for their family and loved ones. The tremors, stiffness, and slow movements can sometimes feel like life is slowing down. But here’s the good news: modern medicine has come a long way. Today, doctors have several effective medications that can significantly reduce these symptoms, helping people live a more active and independent life.

Here are the most commonly used medicines for Parkinson’s disease.

1. Levodopa (with Carbidopa)

Parkinson’s disease happens when the brain doesn’t make enough dopamine, a chemical messenger that controls smooth movement. Since dopamine itself cannot cross from the bloodstream into the brain, doctors use levodopa, which can enter the brain.

Inside the brain, levodopa is converted into dopamine. This newly formed dopamine then stimulates dopamine receptors, improving movement, reducing tremors, stiffness, and slowness.

Because much of levodopa can break down in the body before reaching the brain, it’s usually given with carbidopa, which prevents early breakdown and ensures more levodopa gets to the brain.

Advances in Levodopa Therapy

In recent years, new formulations have made levodopa therapy more convenient and effective:

Crexont (Levodopa + Carbidopa Extended-Release)

According to research published by NIH in 2025, the FDA has approved Crexont, a new long-lasting pill for Parkinson’s disease made by Amneal Pharmaceuticals. It contains immediate- and extended-release levodopa with carbidopa in one tablet to help patients control symptoms with fewer doses.

Long-Acting Injectable Levodopa

 Another recent news article published in July 2025 reports that Scientists from the University of South Australia (UniSA) have developed a long-acting injectable implant that is administered under the skin and delivers a steady dose of levodopa and carbidopa over an entire week, potentially eliminating the need for multiple daily tablets.

Levodopa remains the most effective treatment for Parkinson’s, especially for reducing motor symptoms and improving quality of life.

2. Dopamine Agonists 

Dopamine agonists work by directly stimulating dopamine receptors in the brain, mimicking the effects of dopamine. This improves movement and helps control symptoms. 

Common dopamine agonists include:

• Pramipexole
  
  
• Ropinirole
  
  
• Rotigotine
  
  
• Apomorphine

They are often used in the early stages of Parkinson’s disease, especially for younger patients. These are available in several forms, such as extended-release, immediate-release, or fast-acting options.

Onapgo – A New Dopamine Agonist

Onapgo (apomorphine) is a new dopamine agonist treatment approved by the FDA in February 2025. It is given through a small pump under the skin and provides a steady flow of medicine during the day. This continuous delivery of medicine helps in more consistent control of symptoms. Because it bypasses the stomach, it may also help people who have trouble absorbing oral medicines. 

3. MAO-B inhibitors

MAO-B inhibitors are medicines that work by blocking an enzyme in the brain called monoamine oxidase-B (MAO-B). This enzyme normally breaks down dopamine. By stopping this breakdown, MAO-B inhibitors allow dopamine to stay active longer, helping improve movement and reduce symptoms like stiffness and slowness. 

Common MAO-B inhibitors include:

• Selegiline
  
  
• Rasagiline
  
  
• Safinamide

These medicines can be used alone in the early stages of Parkinson’s disease to provide mild symptom relief, or they can be combined with levodopa in later stages to make its effects last longer. Because they are usually well tolerated, they are often chosen for patients who want a gentler starting option.

4. Anticholinergics

Anticholinergics are the earliest medicines used to treat Parkinson’s symptoms, and they are still commonly prescribed today—either alone or in combination with other drugs. For the body to move normally, acetylcholine and dopamine must stay in balance. Anticholinergics work by blocking acetylcholine, a brain chemical that becomes overactive when dopamine levels are low. By restoring the balance between dopamine and acetylcholine, these medicines help reduce tremors and muscle stiffness.

Common anticholinergics include:

• Trihexyphenidyl
  
  
• Benztropine

5. COMT Inhibitors

COMT inhibitors ) are Parkinson’s medicines that don’t directly improve symptoms but instead help levodopa last longer by preventing it from breaking down too quickly. Normally, an enzyme called COMT breaks down levodopa before it can reach the brain. COMT inhibitors block this enzyme, so more levodopa gets to the brain, giving you smoother and longer-lasting symptom relief. They are not usually used alone but are added to levodopa treatment when symptoms start to “wear off” too quickly.

Common COMT inhibitors include:

• Entacapone
  
  
• Opicapone
  
  
• Tolcapone

6. Amantadine

Amantadine is a medicine that can be used to help people with Parkinson’s disease (PD). It works by increasing dopamine activity in the brain and blocking certain signals that can cause extra movements. In PD, amantadine is often given to reduce dyskinesia—the uncontrolled, jerky movements. It may also help with tremor, stiffness, and “OFF” episodes when symptoms return as other medicines wear off. Amantadine comes in both regular and extended-release forms.