A smoking cessation drug -- cytisine -- may help treat Parkinson's disease or stop its progression in women say researchers including an Indian-origin. The study published in the Journal of Neurochemistry showed that in an animal-based model the drug reduces the loss of dopamine neurons in females which indicates it as potential evidence for the use of the drug to treat Parkinson's disease. What cytisine does is it binds to target receptors but doesn't activate them as efficiently as nicotine said researcher Rahul Srinivasan from the Texas AM University in the US. It keeps the receptors 'occupied' and 'chaperones' them