My husband has been diagnosed with essential tremor, or ET.  What is this, and how is it different from Parkinson's disease?  What is the treatment?
D020329:Essential Tremor / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D010300:Parkinson Disease / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D011433:Propranolol / Q000627:therapeutic use
D011433:Propranolol