Tremor, or shaking movements, may have many causes. Essential tremor is not caused by an underlying disease; thus, it does not mark a progressive or a debilitating problem. Most cases begin before age 25. However, a variety called senile tremor begins in old age. This tremor involves the arms, hands, and face. It usually starts in, and it may remain confined to, one side of the body. It tends to progress slowly.
