| Tremor | Description |
| Essential tremor | Bilateral postural or kinetic tremor of the hands and forearms (≥4 Hz; usually 6 to 12 Hz) or isolated head tremor without evidence of dystonia. Absence of other neurologic signs or recent trauma preceding the onset of tremor. |
| Physiologic tremor | Enhanced physiologic tremor. High frequency (10 to 12 Hz), presence of known cause (eg, medications, hyperthyroidism, hypoglycemia). |
| Parkinson disease | Mixture of rest and action tremors; occasionally action tremor alone. Leg or foot tremor more common than with essential tremor, usually does not produce head tremor. Frequency 4 to 6 Hz. |
| Orthostatic tremor | Postural tremor in the torso and lower limbs while standing; may also occur in the upper limbs. Suppressed by walking. Tremor is high frequency (14 to 20 Hz) and synchronous among ipsilateral and contralateral muscles. |
| Cerebellar tremor | Postural, intention, or action tremor. Relatively low frequency (3 to 4 Hz). Associated with ataxia and dysmetria. |
| Neuropathic tremor | Variable tremor type and frequency, usually postural and kinetic tremor in the involved extremities. Other signs of peripheral neuropathy present. |
| Rubral or midbrain tremor | Mixture of rest, postural, and intention tremor with frequency of 2 to 5 Hz. Always associated with signs of brainstem or cerebellar damage. |
