For treating newly diagnosed Parkinson’s disease, the drug that has been in use the longest offers a slight edge compared with newer medications, according to a head-to-head comparison study in The Lancet.
The “oldie but goodie” medications for treating the muscle rigidity and tremors caused by Parkinson’s contain levodopa (Parcopa, Sinemet). But levodopa causes involuntary muscle tics, known as dyskinesia. Concern about dyskinesia drove development of alternative medications, such as dopamine agonists and monoamine oxidase B inhibitors (MAOBIs).
In a clinical trial, 1,620 people with new Parkinson’s were chosen randomly to receive one of the three drugs. After seven years, those who took levodopa scored higher on a standard test for mobility than those taking the other two drugs. Also, those on levodopa were much less likely to stop taking their medication than those on dopamine agonists or MAOBIs, most likely because of side effects.
Those on levodopa did experience more dyskinesia than the other groups. This might have been more acceptable to the participants than side effects from the other drugs. Dopamine agonists, for instance, are more likely to trigger impulsive behaviors, including gambling and sexual thoughts or actions.