Propranolol reduces tremors in Parkinson's disease

The standard medication levodopa does not always work against tremors in Parkinson's disease, especially in stressful situations. Propranolol, however, does work during stress, providing insight into the role of the stress system in tremors. MRI scans reveal that propranolol directly inhibits activity in the brain circuit that controls tremors. Doctors may consider this medication when levodopa is ineffective.