Parkinson’s disease can’t be cured, but medications can help control your symptoms, often dramatically. In some later cases, surgery may be advised. Your doctor also may recommend lifestyle changes, especially ongoing aerobic exercise. In some cases physical therapy that focuses on balance and stretching also is important.
Medications can help you manage problems with walking, movement and tremor by increasing your brain’s supply of dopamine. However, dopamine can’t be given directly, as it can’t enter your brain.
You may have significant improvement of your symptoms after beginning Parkinson’s disease treatment. Over time, however, the benefits of drugs frequently diminish or become less consistent, although symptoms usually can continue to be fairly well controlled.
Your doctor may prescribe medications, which may include:
- Carbidopa-levodopa (Parcopa). Levodopa, the most effective Parkinson’s disease medication, is a natural chemical that passes into your brain and is converted to dopamine. Levodopa is combined with carbidopa, which protects levodopa from premature conversion to dopamine outside your brain, which prevents nausea. In Europe, levodopa is combined with a similar substance, benserazide (Madopar). Side effects include nausea or a drop in blood pressure when standing (may result in faintness).
After years, as your disease progresses, the benefit from levodopa may become less stable, with a tendency to wax and wane (“wearing off”). Also, you may experience involuntary movements (dyskinesia) after taking higher doses of levodopa. Your doctor may lessen your dose or adjust the times of your doses to control these effects.
- Dopamine agonists. Unlike levodopa, dopamine agonists don’t change into dopamine. Instead, they mimic dopamine effects in your brain. They aren’t as effective in treating your symptoms as levodopa. However, they last longer and may be used with levodopa to smooth the sometimes off and on effect of levodopa.
Dopamine agonists include pramipexole (Mirapex) and ropinirole (Requip). A short-acting injectable dopamine agonist, apomorphine (Apokyn), is used for quick relief.
The side effects of dopamine agonists are similar to carbidopa-levodopa, but also include hallucinations, swelling, sleepiness or compulsive behaviors such as hypersexuality, gambling and eating. If you’re taking these medications and you start behaving in a way that’s out of character for you, talk to your doctor.
- MAO B inhibitors. These medications include selegiline (Eldepryl, Zelapar) and rasagiline (Azilect). They help prevent the breakdown of brain dopamine by inhibiting the brain enzyme monoamine oxidase B (MAO B). This enzyme metabolizes brain dopamine. Side effects are uncommon, but may rarely include nausea or headaches. When added to carbidopa-levodopa, these medications can increase the risk of hallucinations. These medications can’t be used in combination with most antidepressants or certain narcotics, due to potentially serious reactions. Check with your doctor before taking any additional medications with a MAO B inhibitor.
- Catechol O-methyltransferase (COMT) inhibitors. Entacapone (Comtan) is the primary medication from this class. This medication mildly prolongs the effect of levodopa therapy by blocking an enzyme that breaks down levodopa. The side effects are primarily those due to an enhanced levodopa effect, including an increased risk of involuntary movements (dyskinesias). Tolcapone (Tasmar) is another COMT inhibitor that is rarely prescribed due to a risk of serious liver damage and liver failure.
- Anticholinergics. These medications were used for many years to help control the tremor associated with Parkinson’s disease. Several anticholinergic medications are available, including benztropine (Cogentin) and trihexyphenidyl. However, their modest benefits are often offset by side effects such as impaired memory, confusion, hallucinations, constipation, dry mouth and impaired urination.
- Amantadine. Doctors may prescribe amantadine alone to provide short-term relief of symptoms of mild, early-stage Parkinson’s disease. It also may be added to carbidopa-levodopa therapy for people in the later stages of Parkinson’s disease, to help control involuntary movements (dyskinesia) induced by carbidopa-levodopa. Side effects may include a purple mottling of the skin, ankle swelling or hallucinations.
- Deep brain stimulation. In deep brain stimulation (DBS), surgeons implant electrodes into a specific part of your brain. The electrodes are connected to a generator implanted in your chest that sends electrical pulses to your brain and may help improve many of your Parkinson’s disease symptoms. Your doctor may adjust your settings as necessary to treat your condition. Surgery may involve risks, including infections, stroke or brain hemorrhage.
Deep brain stimulation is most often a procedure to treat people with advanced Parkinson’s disease who have unstable medication (levodopa) responses. DBS can help stabilize medication fluctuations, reduce or eliminate involuntary movements (dyskinesia), reduce tremor, reduce rigidity, and improve slowing of movement. DBS is very effective in controlling erratic and fluctuating responses to levodopa or for controlling dyskinesias that can’t be controlled with medication adjustments. However, it’s not helpful for treating problems that don’t respond to levodopa therapy, apart from tremor (tremor may be controlled even if not very responsive to levodopa).