Your family member will need a drug treatment plan tailored to her specific needs to achieve the best results. That's why it's so important early on to try to see a movement disorders specialist, "who really knows the disease, and when and how to use which medications," says Kelly E. Lyons, a research associate professor of neurology at the University of Kansas Medical Center in Kansas City. "It makes a big difference long-term in how patients do."

In terms of side effects, it's important to recognize the difference between the wiggly, almost dance-like motions of dyskinesias and a Parkinson's tremor, which tends to shake at a fairly constant rhythm, says Lyons. "The tremor is actually a symptom of the disease. The dyskinesia is a side effect of the drugs," she says. If your family confuses the two things when communicating with the physician, it could lead him down the wrong path in adjusting the drug regimen.

Each Parkinson's disease medication comes with a range of potential adverse effects, and it's a good idea to be aware of the problems a patient may experience. For instance, levodopa and dopamine agonists may cause nausea, vomiting, sleepiness, or insomnia (which all usually fade with time), as well as dizziness or fainting from low blood pressure. In some patients with advanced Parkinson's disease, both kinds of drugs may also cause hallucinations and psychosis; this risk is greater with the dopamine agonists.

Side effects should be discussed with your family member's doctor. He can try adjusting the dose, switching to another drug, or adding on other treatments for the problem at hand. For more details on Parkinson's drugs and their side effects, visit the National Parkinson Foundation and download its free publication on medications.