AAN Updates Recommendations for Early Parkinson Disease Treatment

Counseling should be provided to individuals with early Parkinson disease on the benefits and risks of initiating treatment.

The American Academy of Neurology (AAN) has issued updated guidelines on initiating dopaminergic therapy for motor symptoms in early Parkinson disease.

According to the guidelines, counseling should be provided to individuals with early Parkinson disease on the benefits and risks of initiating treatment with levodopa, dopamine agonists, and monoamine oxidase B (MAO-B) inhibitors

Initial treatment with levodopa was found to provide greater benefit for motor symptoms compared with either dopamine agonists or MAO-B inhibitors. While levodopa is more likely to induce dyskinesia during the first 5 years of treatment compared with dopamine agonists, the prevalence of severe or disabling dyskinesia was found to be low during this time. To optimize benefit and reduce the risk of dyskinesia, the lowest effective dose of levodopa should be prescribed.

Compared with levodopa, treatment with dopamine agonists was associated with a higher risk of impulse control disorders (eg, compulsive gambling, eating, shopping, sexual activity, hallucinations). There was also a higher risk of excessive daytime sleepiness associated with the use of dopamine agonists.

Individuals treated with dopamine agonists or MAO-B inhibitors were also more likely to discontinue treatment due to side effects compared with levodopa. Moreover, patients treated with MAO-B inhibitor monotherapy were more likely to require additional therapy within 2 to 3 years.

“We carefully reviewed the available research on the effectiveness and possible risks of medications to treat motor symptoms in people with early Parkinson disease and found that levodopa is usually the best first treatment for these symptoms,” said guideline lead author Tamara Pringsheim, MD, MSc, of the University of Calgary in Alberta, Canada, and a Fellow of the American Academy of Neurology. “Still, there are side effects with levodopa as well as other drugs, so it is important that a person newly diagnosed with Parkinson disease discusses all options with their neurologist before deciding on the best treatment plan for them.”


  1. AAN issues guideline for treatment of Early Parkinson’s disease. News release. American Academy of Neurology. Accessed November 16, 2021. https://www.prnewswire.com/news-releases/aan-issues-guideline-for-treatment-of-early-parkinsons-disease-301424702.html
  2. Pringsheim T, Day GS, Smith DB, et al. Dopaminergic therapy for motor symptoms in early Parkinson disease practice guideline summary: A report of the AAN guideline subcommittee. Neurology. Published online November 15, 2021. doi: 10.1212/WNL.0000000000012868