Drugs Used to Treat Parkinson's Disease

According to the Parkinson's Disease Foundation, up to one million American citizens suffer from Parkinson's disease, a degenerative disease that affects your central nervous system. There are more than 15 different medications on the market that help to minimize symptoms and increase a patient's quality of life.

Levodopa

• Thirty years ago, levodopa transformed the face of Parkinson's treatments as it was one of the first medications used. Levodopa works by being changed into dopamine within your basal ganglia. The medication is usually combined with carbidopa for maximum benefit. Long-term use may lead to an "on/off" effect due to fluctuating levels of the medication in your blood.

  Possible side effects include uncontrolled movement of the limbs or mouth, orthostatic hypotension, nightmares, heart palpitations, nausea, flushing of the skin, hallucinations, drowsiness, constipation and confusion. Levodopa-carbidopa treatments cannot be discontinued abruptly or you may experience serious, even life-threatening, effects.

Dopamine Agonists

• Medications that imitate the actions of dopamine within your brain are called dopamine agonists. These are usually used during the early stages of Parkinson's disease and are often combined with levodopa later. The market includes Requip (ropinirole) and Mirapex (pramipexole). Possible side effects include nausea, hallucinations, orthostatic hypotension, confusion, drowsiness and involuntary movements.

COMT and MAO-B Inhibitors

• Stopping dopamine from being broken down, thereby increasing available levels of dopamine, is another treatment option. COMT inhibitors and MAO-B inhibitors perform exactly this function.

  Side effects of MAO-B inhibitors like rasagiline or selegiline include edema, drowsiness, nausea and insomnia. Taking an MAO-B inhibitor at high doses while consuming products containing tyramine may lead to a serious condition called hypertensive crisis, which is characterized by a spike in blood pressure and an acute headache.

  COMT inhibitors like entacapone or tolcapone may cause back pain, confusion, upset stomach, involuntary movement, changes in urine coloration and diarrhea.

Anticholinergic Medications

• Anticholinergic medications may reduce acute tremors by blocking acetylcholine in your body. Medications including benzotropine and trihexyphenidy (along with certain tricyclic antidepressants and antihistamines) can complement levodopa treatment. They do not, however, affect rigidity or slow movements.

  Side effects include blurry vision, dry mouth, constipation, dizziness, altered mental state, urinary incontinence and problems urinating. Elderly patients are more susceptible to experiencing adverse effects.

Antiviral Medications and Beta-Blockers

• Antiviral medications like amantadine are sometimes used in the disease's early stages and are often prescribed along with levodopa to reduce the involuntary movements that can accompany the medication.

  Beta-blockers like propranolol may be prescribed to alleviate severe tremors. Possible side effects include blood sugar problems, heart failure, bronchospasm and bradycardia.

Considerations

• Working closely with your doctor and monitoring your symptoms are crucial in determining the right medications to treat your Parkinson's symptoms. Medications are also available to alleviate symptoms of depression or other other psychological symptoms that may be concurrent with the disease. While no medications have been found to halt the progression of the disease, research remains ongoing and hope remains.