Medication and Treatment
When to Start Medication Treatment
Medications do not cure or prevent Parkinson’s disease progression. However, they are effective at suppressing symptoms. There is no consensus on when to start medication, however, most specialists recommend waiting until symptoms begin to interfere with daily activities before starting medications.
Medical therapies are largely aimed at stimulating brain dopamine and often result in rapid symptomatic improvement in most patients.
- Levodopa is a chemical cousin of dopamine, a neuro-hormone or chemical that is produced naturally in the brain and regulates movement. Enzymes in the brain convert levodopa into dopamine. Levodopa is the most effective drug for the treatment of most Parkinson’s disease symptoms. As the disease progresses you may have to take higher doses of the medication or take it more frequently. Levodopa is always combined with carbidopa (or benserazide in other countries), which reduces nausea associated with levodopa. Other potential side effects include dry mouth, dizziness, and orthostatic hypotension (i.e., lowering of blood pressure upon standing). Long-term use can cause complications including abnormal involuntary movements (i.e., dyskinesia) and psychiatric effects (i.e., hallucinations).
- Dopamine Agonists: Ropinirole, pramipexole, and rotigotine are dopamine agonists, which stimulate dopamine receptors in the brain. These medications are better tolerated by younger patients. We start these medications slowly and adjust the dose to suit each individual. Side effects of all dopamine agonists include drowsiness, nausea, vomiting, dry mouth, dizziness, impulse control disorders, swelling in the legs, and orthostatic hypotension. At higher doses, dopamine agonists may cause confusion, hallucinations, or psychosis. We will talk to you about the risks of driving or performing other activities that require high levels of alertness.
Your physician may prescribe other medications that include the following:
- Anticholinergics: Used to minimize tremors or rigidity by relaxing muscle spasms. We don’t prescribe these drugs for very elderly patients or those with dementia, because they can cause increased confusion and increase the risk for falls. Other potential side effects include dry mouth, sedation, delirium, hallucinations, constipation, and urinary retention.
- COMT Inhibitors: Entcapone and opicapone are used to help prolong the effects of levodopa by reducing its breakdown. Entacapone is taken with each dose of levodopa; opicapone is taken once a day. Side effects include discoloration of urine, diarrhea, and weight loss.
- MOA(b) Inhibitors: Selegiline, rasagiline, and safinamide are used to help prolong the effects of levodopa by reducing its breakdown in the brain. Side effects may include hallucinations, orthostatic hypotension, insomnia and nausea (related to the increased availability of levodopa). The FDA has issued a warning for those taking these drugs as they can potentially cause serotonin syndrome if combined with certain antidepressants. Serotonin syndrome can cause extremely high blood pressure and other symptoms. If you are on either of these medications. Please contact us to see if you are at risk.
- Amantadine: Used to reduce dyskinesia (involuntary movements related to the use of levodopa) and other motor symptoms. Side effects include dry mouth, difficulty concentrating, confusion, insomnia, nightmares, agitation, and hallucinations. Amantadine may cause swelling in the extremities and mottled skin.
- Istradefylline: Used to help prolong the effects of levodopa by blocking adenosine receptors in the brain. Side effects include dyskinesia, hallucinations, compulsive behaviors (related to increased dopamine function).
- Quetiapine: An anti-psychotic medication used to block the hallucinations caused by Parkinson’s disease medications. Most other antipsychotic medications (except clozapine) can make Parkinson’s disease symptoms worse. This is not a significant problem with low doses of quetiapine. Quetiapine’s side effects include sedation and constipation.
- Pimavanserin: A novel therapy for the treatment of hallucinations and delusions associated with PD psychosis. The most commons side effects include peripheral edema, nausea, confusion, constipation, and gait disturbance.
- Rescue medications: Some patients with Parkinson’s disease experience sudden wearing off of their medications. Apomorphine and inhaled levodopa are two short-acting medications that can be used to address such off periods. These do not replace your daily mediations, but are used as additional therapies to control motor function.
Managing Medication Side Effects
Most medications to treat Parkinson’s disease are well tolerated, however, people may experience side effects. It is important to discuss side effects with your physician as there are many ways to address them.
- Nausea: We do not prescribe “standard” anti-nausea medications to patients with Parkinson’s disease since it blocks dopamine in the brain, which can make symptoms worse. Some patients experience nausea as a side effect of dopamine-controlling medications. We recommend that you try taking your medication with meals that do not contain protein. If that does not work, we can adjust your medications to minimize nausea. Most people find that the side effect wears off or they can prevent nausea and continue to benefit from their medications.
- Excessive Sweating: Excessive sweating is an occasional side effect of levodopa. We can adjust your medication regimen to treat this symptom in several ways, for example, by reducing your levodopa dose or adding a dopamine agonist.
Complementary and Alternative Medicine
- Advanced research is underway to find “neuroprotective” drugs or supplements that can prevent or slow down nerve cell damage to stop the disease from progressing. Please discuss with your physician before taking any drug-supplements.