This patient has essential tremor involving the arms. Essential tremor is a high-frequency rhythmic oscillation of the limb, head or voice that occurs while maintaining a posture such as when the hands are outstretched. This type of tremor has many other names. When hereditary it is called familial; it is also called postural, senile and action tremor. Essential tremor is improved with alcohol and worse with anxiety, caffeine and lack of sleep. The pathophysiologic mechanism of essential tremor is unknown.