Drug-induced tremor is involuntary shaking due to the use of medication. Involuntary means you shake without trying to do so.

See also:

• Essential tremor
• Familial tremor
• Tremor

Drug-induced tremors are a simple muscular response to certain medications. Drugs that can cause tremors include the following:

• Mood stabilizers such as lithium carbonate
• Bronchodilators such as theophylline and Alupent
• Anticonvulsants such as valproic acid and Depakote
• Immunosuppressants such as cyclosporine
• Stimulants such as caffeine

The tremors may affect the hands, arms, head, eyelids, or other muscles. The tremors rarely affect the legs or feet.

The shaking usually involves small, rapid movements -- more than 5 times a second.

The tremors may:

• Occur when you move (action-related tremor), and may be less noticeable with rest
• Come and go, but generally get worse as you age
• Disappear during sleep
• Get worse with stress, caffeine, and certain medications
• Not affect both sides of the body the same way

Head nodding may also be a symptom of tremors. If the tremors affect the voice box, you may have a shaking or quivering sound to your voice.

Your doctor can make the diagnosis by performing a physican exam and asking questions about your medical and personal history.

A physical exam will show shaking with movement. There are usually no problems with coordination or mental function.

Further tests may be needed to rule out other reasons for the tremors. Other causes of tremors may include:

• Alcohol withdrawal
• Cigarette smoking
• Hyperthyroidism
• Parkinson's disease
• Pheochromocytoma
• Too much caffeine
• Wilson's disease

Blood tests and imaging studies (such as a CT scan of the head, brain MRI, and x-rays) are usually normal.

Drug-induced tremors go away when you stop taking the medicine thats causing the shaking.

Never stop taking any medicine without first talking to your doctor.

Treatment or changes in medications may not be required at all if the tremors are mild and do not interfere with daily activity. Different doses or similar medications may not cause the tremor.

Drug-induced tremor is not a dangerous condition, but some patients find the tremors annoying and embarrassing.

Severe tremor can interfere with daily activities, especially fine motor skills such as writing, and other activities such as eating or drinking.

Call your health care provider if you are taking a medication and tremors develop that interfere with activity or are accompanied by other symptoms.

Always tell your doctor about the medicines you take. Over-the-counter drugs should be taken with caution, especially those that contain stimulants or a medicine called theophylline.

Caffeine can make tremors worse. Avoid caffeinated drinks such as coffee, tea, and soda, and other stimulants.