Eight open-label studies and four placebo-controlled studies addressed this question. Seven of the eight open-label showed improvement in motor symptoms, but the placebo-controlled studies were all negative.
A new study was presented at the 4th World Parkinson Congress by Gabriel Villafane. It involved high doses (90 mg per day) of transdermal nicotine and measured the UPDRS for “off” motor scores. Blinded video rating was done.
At 39 weeks, there was no statistically significant difference in motor scores as well as a quality of life measure. There seemed to be a reduction in levodopa doses, reduction in dyskinesias, and improvement in activities of daily living. As expected, adverse effects were more common in the nicotine group.