Current and emerging treatments in Parkinson's disease

Parkinson's disease is one of the commonest neurodegenerative diseases of the elderly. The discovery of dopamine deficiency from the degeneration of substantia nigra neurons revolutionised treatment in the early 70's.

This review is based on Medline search with Keywords (Parkinson's disease, treatment, therapy, surgery).

Levodopa remains the gold standard of medications. New drugs include recently introduced dopamine agonists like ropinorole and pramipexole, and COMT inhibitors. The role of selegiline in neuroprotection remains controversial. Dopamine agonist monotherapy may delay the onset of motor fluctuations. Levodopa may be associated with the earlier onset of motor complications such as dyskinesias, and it may be preferable to delay its use in younger patients. In older patients, especially those with significant disability, levodopa use should not be delayed. Surgical therapies such as pallidotomy, bilateral subthalamic deep brain stimulation and foetal transplantation can be considered for those who fail medical therapy. Molecular science techniques including gene therapy, neurotrophic factors, stem cell technology form the next frontier of Parkinson's research.

No new medication has proven more efficacious than levodopa. More controlled trials are required in Parkinson's surgery to reach definite conclusions about its effects and long-term results.