Essential tremor (ET) is a disease that progresses slowly and usually presents either in late adolescence to early 20s or in the patient’s 40s; if it develops, it will almost certainly appear by age 65 (Damian, Hancu & Gregorian, 2009). Its cause is unknown and may have a genetic component. Typically, ET patients exhibit only that one symptom. If other symptoms are present, a differential diagnosis should be considered. Typical of ET is that the tremors gradually worsen over time, that they disappear when the patient is asleep, that the patient has some level of voluntary control, and that the tremors may start on one side and progress to the other, with some level of asymmetry between the sides (Damian et al., 2009).

In Parkinson’s disease, the tremors are usually experienced when at rest, and decrease when the patient uses the hand or arm. In ET, the tremors increase with action and holding against gravity, but decrease when at rest. Parkinson’s tremors also do not involve the head or voice, whereas ET tremors do (Damien et al., 2009). Parkinson’s also can involve a “mask-like” expression—rigidity of the facial muscles—that makes it difficult to determine the patient’s reactions and mood (Heisters, 2007). Finally, whereas ET has only the one symptom of tremors, Parkinson’s includes rigidity, particularly of the face, slow movements (bradykinesia), sleep disorders, bladder & bowel problems, and other symptoms (Heisters, 2007).

There is no cure for ET but some medications may help; usually surgery is considered only if tremors interfere extensively in daily activities. Assistance from an occupational therapist may offer suggestions for altering ways of doing daily activities to reduce the impact of the tremors. ET does not appear to affect patient longevity, though quality of life may be impacted.
A diagnosis of Parkinson’s disease often leaves patients very frightened; a survey reported by Gofton & Jog (2008) indicated that the most frequent emotional response to such a diagnosis was to be “frightened for the future,” closely followed by “shock,” feeling “sad or depressed” and “denial.” Parkinson’s is a life-changing disease, so it is essential that patients’ questions be answered (Gofton & Jog, 2007).

As with ET, there is no cure for Parkinson’s. In early stages, no treatment may be necessary. Such techniques a exercise, physical therapy and occupational therapy to help overcome the symptoms are useful. Medications such as levodpoa can be used, but only for a few years before it develops side effects. Other medications can be used. If Parkinson’s is suspected, it is important to refer the patient to a doctor experienced with the disease before starting any medications (Damian et al., 2009).