Amitriptyline comes as a tablet to take by mouth. It is usually taken one to four times a day and may be taken with or without food. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take amitriptyline exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Continue to take amitriptyline even if you feel well. Do not stop taking amitriptyline without talking to your doctor, especially if you have taken large doses for a long time. Your doctor probably will want to decrease your dose gradually. This drug must be taken regularly for a few weeks before its full effect is felt.

Side effects from amitriptyline are common:

upset stomach
drowsiness
weakness or tiredness
excitement or anxiety
insomnia
nightmares
dry mouth
skin more sensitive to sunlight than usual
changes in appetite or weight
Tell your doctor if any of these symptoms are severe or do not go away:

constipation
difficulty urinating
frequent urination
blurred vision
changes in sex drive or ability
excessive sweating
If you experience any of the following symptoms, call your doctor immediately:

jaw, neck, and back muscle spasms
slow or difficult speech
shuffling walk
persistent fine tremor or inability to sit still
fever
difficulty breathing or swallowing
severe skin rash
yellowing of the skin or eyes
irregular heartbeat