How do you approach a patient with both a resting and action tremor, suggestive of PD and essential tremor together?

This is a wonderful question. To answer this question, we first have to look at the underlying etiology that leads to action tremor in PD. The hallmark of Parkinson's Disease (PD) is rest tremor, and about 75% of patients with PD have rest tremor at some point in their disease course (typically more earlier on). However, as evidenced by the United Parkinson's Disease Rating Scale (UPDRS), individuals with PD can have kinetic and postural tremor. Specifically, this is reported in 33-46% of patien...