What it is used for

Nerve pain (neuropathic pain)
Preventing migraine
Preventing tension-type headaches
Depression (at higher doses, now rarely used for this)
Bedwetting in children (rarely)

Read our guides:

Off-label uses

Doctors sometimes prescribe a medicine for a condition it is not officially licensed for. This is called off-label use. It is legal and common when there is good evidence it helps, and your doctor should explain why they are suggesting it.

Fibromyalgia
Irritable bowel syndrome (IBS), at low doses
Long-term pain, such as back pain
Sleep problems linked to pain

How it works

Amitriptyline increases the levels of serotonin and noradrenaline, two chemical messengers in the brain and spinal cord. This changes how pain signals are passed along nerves, and at higher doses it can improve mood.

Side effects

Like all medicines, Amitriptyline can cause side effects, although not everyone gets them. Many are mild and ease after the first few weeks.

Common side effects

feeling sleepy
dry mouth
constipation
difficulty peeing
headache
feeling dizzy
weight gain

Tell your doctor or pharmacist if these bother you or do not go away.

Serious side effects

These are rare. Call 111 or contact your doctor straight away if you get:

a fast or irregular heartbeat
thoughts of harming yourself or ending your life
yellowing of the skin or eyes
eye pain with changes in vision

Call 999 if you have signs of a serious allergic reaction, such as swelling of your lips, mouth, throat or tongue, or trouble breathing.

You can report any side effect to the Yellow Card scheme, run by the medicines regulator.

Stopping and withdrawal

Important safety information

It is usually taken in the evening because it causes drowsiness.
It can be dangerous in overdose. Keep it safely away from others.
Avoid alcohol, as it increases drowsiness.

Questions about your medicine?

A pharmacist can answer questions about your medicines for free, without an appointment. You can also ask your GP for a medication review. Check if you can get free prescriptions.