Amitriptyline for pain and migraine

NHS Choices

August 3, 2018

About amitriptyline for pain

Amitriptyline is a medicine used to treat pain.

It's especially good for nerve pain such as back pain and neuralgia.

It can also help prevent migraine attacks.

Amitriptyline is available on prescription. It comes as tablets and as a liquid.

Amitriptyline is also used to treat depression. Read about amitriptyline for depression.

Key facts

Amitriptyline is widely used to treat depression, but at lower doses it's also very good for treating pain.
Amitriptyline can make you feel sleepy so it's best to take it in the evening or before you go to bed.
You may notice a difference after a week or 2 but it can take 6 weeks for amitriptyline to work as a painkiller.
Amitriptyline can cause extra side effects if you stop taking it suddenly. Talk to your doctor if you're thinking of stopping taking amitriptyline.

Who can and can't take amitriptyline

Amitriptyline can be taken by most adults. It can also be taken by children aged 2 to 17 years for some types of nerve pain.

Amitriptyline isn't suitable for some people. Check with your doctor before starting to take amitriptyline if you:

have had an allergic reaction to amitriptyline or any other medicines in the past
have a heart problem - amitriptyline can make some heart problems worse
have a rare illness called porphyria
have liver or kidney problems
have epilepsy - amitriptyline can increase seizures
have ever taken any medicines for depression - some rarely-used antidepressants can interfere with amitriptyline
are trying to become pregnant, are already pregnant or you are breastfeeding - amitriptyline isn't always recommended in pregnancy or while breastfeeding
have an eye problem called glaucoma - amitriptyline can increase the pressure in your eye
have thoughts about harming yourself or ending your life

If you have diabetes, amitriptyline may change your blood sugar level. Check your blood sugar more often for the first few weeks of treatment with amitriptyline. Talk to your diabetes doctor if the reading goes too high or low.

How and when to take it

It's usual to take amitriptyline once a day before bedtime because it can make you feel sleepy. If you find that you are still feeling drowsy in the morning you could try taking it earlier in the evening.

This medicine doesn't usually upset your tummy. You can take it with or without food.

Swallow the tablet with a drink of water - if you chew it, it tastes bitter.

How much will I take?

Amitriptyline tablets come in 3 different strengths - 10mg, 25mg or 50mg.

Liquid amitriptyline comes in 3 different strengths containing 10mg, 25mg or 50mg of amitriptyline in a 5ml spoonful.

The usual starting dose in adults and children aged 12 to 17 years is 10mg a day. This dose can be increased if you need better pain relief.

The starting dose for younger children depends on their weight and symptoms.

The maximum dose of amitriptyline for treating pain is 75mg a day. It can be higher if you're taking it to prevent migraine.

What if I forget to take it?

If you forget a dose, take it as soon as you remember, unless it's nearly time for your next dose. In this case, just leave out the missed dose and take your next dose as normal.

If amitriptyline makes you sleepy and you need to drive or use tools or machinery, leave out the missed dose and carry on with the next dose as normal.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.

What if take too much?

Ask your doctor for advice straight away. An overdose can lead to potentially serious symptoms such as:

vomiting
shaking
drowsiness
change in your heartbeat
seizures

Side effects

Like all medicines, amitriptyline can cause side effects in some people, but many people have no side effects or only minor ones.

Some of the common side effects of amitriptyline gradually improve as your body gets used to it.

Common side effects

Because the dose of amitriptyline for pain is lower than the dose for depression the common side effects tend to be milder and go away within a few days.

Keep taking the medicine but talk to your doctor or pharmacist if these side effects bother you or don't go away:

constipation
dizziness
dry mouth
feeling sleepy
difficulty peeing
headache

Serious side effects

It happens rarely, but some people have a serious side effect after taking amitriptyline.

Call a doctor straight away if you get:

a fast or irregular heartbeat
yellow skin, or the whites of your eyes go yellow - these can be signs of a liver problem
a headache, feel confused or weak, get muscle cramps or a seizure - these can be signs of a low sodium level in your blood
thoughts about harming yourself or ending your life
eye pain, a change in your eyesight, swelling or redness in or around the eye
severe constipation or you're unable to pee and it's causing severe tummy pain
weakness on one side of your body, trouble speaking or thinking, loss of balance or blurred eyesight - these can be signs of a stroke

If you suspect that you or someone else is having a stroke, phone 999 immediately and ask for an ambulance.

Serious allergic reaction

In rare cases, it's possible to have a serious allergic reaction to amitriptyline.

A serious allergic reaction is an emergency. Contact a doctor straight away if you think you or someone around you is having a serious allergic reaction.

The warning signs of a serious allergic reaction are:

getting a skin rash that may include itchy, red, swollen, blistered or peeling skin
wheezing
tightness in the chest or throat
having trouble breathing or talking
swelling of the mouth, face, lips, tongue or throat

These are not all the side effects of amitriptyline. For a full list see the leaflet inside your medicines packet.

You can report any suspected side effect to the UK safety scheme.

How to cope with side effects

What to do about:

constipation - eat more high-fibre foods such as fresh fruit and vegetables and cereals. Try to drink several glasses of water or another non-alcoholic liquid every day. If you can, it may also help to do some exercise. Watch a short video on how to treat constipation.
dizziness - this is probably due to low blood pressure. Drink plenty of water or a non-alcoholic drink. Do not stand up too quickly after sitting or lying down.
dry mouth - chew sugar-free gum or sugar-free sweets.
feeling sleepy or tired - take amitriptyline in the evening and cut down the amount of alcohol you drink. Don't drive or use tools or machinery if you're feeling this way.
difficulty peeing - relax when you try to pee. Don't try to force the flow of urine. If it doesn't happen, try again later. Talk to your doctor urgently if you can't pee at all.
headache - make sure you rest and drink plenty of fluids. Don't drink too much alcohol. Talk to your doctor if the headaches last longer than a week or are severe.

Pregnancy and breastfeeding

Amitriptyline is generally not recommended in pregnancy or while breastfeeding. Your doctor will only prescribe amitriptyline for your pain while you're pregnant or breastfeeding if the benefits of taking the medicine outweigh the risks.

Amitriptyline has been linked with a small risk of problems for the unborn baby if you take it in early or late pregnancy.

Talk to your doctor as there may be other painkillers you can take instead of amitriptyline.

Paracetamol is usually the first choice of painkiller if you're pregnant or breastfeeding. Read more about paracetamol in pregnancy.

For more information about how amitriptyline can affect you and your baby during pregnancy, read this leaflet on the Best Use of Medicines in Pregnancy (BUMPS) website.

Amitriptyline and breastfeeding

Amitriptyline is not usually recommended if you're breastfeeding.

Amitriptyline gets into breast milk. It's been linked with side effects like sleepiness in breast fed infants.

Talk to your doctor if you want to breastfeed. There may be other medicines that you can take instead of amitriptyline.

Tell your doctor if you're trying to get pregnant, are already pregnant or if you're breastfeeding.

Cautions with other medicines

Many medicines and amitriptyline can interfere with each other and increase the chances of side effects.

Tell your doctor if you have ever taken any medicines for depression. Some rarely-used antidepressants can interfere with amitriptyline to cause very high blood pressure even after you have stopped taking them.

Make sure that your doctor and pharmacist know you're taking amitriptyline before starting or stopping any other medicine.

Mixing amitriptyline with herbal remedies and supplements

Do not take St John's wort, the herbal remedy for depression, while you are being treated with amitriptyline. It will increase your risk of side effects.

Tell your doctor or pharmacist if you are taking any other medicines, including herbal remedies, vitamins or supplements.

Common questions

How does amitriptyline work?

Amitriptyline is from a group of antidepressants called tricyclic antidepressants. It's thought to work by increasing a chemical called serotonin in the brain. This can improve your mood. It can also change the way that your nerves receive pain signals so pain goes away.

When will I feel better?

You may sleep better straight away. But it usually takes a week or so for pain to begin to wear off. It can take between 4 and 6 weeks before you feel the full benefits.

Do not stop taking amitriptyline after 1 to 2 weeks just because you feel it's not helping your symptoms. Give it at least 6 weeks to work.

How will it make me feel?

Many people sleep better while they're taking amitriptyline.

Although amitriptyline is an antidepressant, it's given in lower doses to help pain. Taking amitriptyline as a painkiller won't change your personality or make you feel any different.

How long will I take if for?

Once you're feeling better you'll probably continue to take amitriptyline for as long as it's working for you. Some people take it for many months and even for years.

Is it safe to take for a long time?

Amitriptyline is safe to take for a long time. There don't seem to be any lasting harmful effects from taking it for many months or years.

Is it addictive?

Amitriptyline isn't addictive but you can get extra side effects if you stop taking it suddenly.

What will happen when I stop taking it?

You may get extra side effects when you stop taking amitriptyline, especially if you stop taking it suddenly. These side effects are a reaction to coming off the medicine.

The side effects are usually harmless but unpleasant. To help prevent them, your doctor will probably recommend reducing your dose gradually over several weeks - or longer, if you have been taking amitriptyline for a long time.

Don't stop taking amitriptyline suddenly, or without talking to your doctor.

Will I gain or lose weight?

Amitriptyline can change how hungry you feel. Some people feel more hungry when they're taking it - others feel less hungry. So your weight may change when you first start taking it.

If you start to have problems with your weight while taking amitriptyline, talk to your doctor or pharmacist.

Can I drive or ride a bike?

Some people feel sleepy while they're taking amitriptyline. It might be best to stop driving and cycling for the first few days of treatment until you know how this medicine makes you feel.

Are there other treatments that could help?

Antidepressants like amitriptyline are just one of several ways to treat nerve pain or prevent migraine. Other treatments include:

painkillers such as paracetamol
medicines that are usually used for epilepsy such as pregabalin
medicines that are usually used to treat high blood pressure such as propranolol
physiotherapy

Choosing a treatment that's most suitable for you depends on:

how long you've had the pain
your symptoms
what medicines have worked or not worked for you in the past

Can I drink alcohol with it?

You can drink alcohol while taking amitriptyline but it may make you feel sleepy. It might be best to stop drinking alcohol until you see how the medicine makes you feel.

Is there any food or drink I need to avoid?

You can eat and drink normally while taking amitriptyline.

Will it affect my contraception?

Amitriptyline does not affect any type of contraception including contraceptive pills and the morning after pill.

Will it affect my sex life?

Some people have sex-related problems while they take amitriptyline. They include:

men having problems with getting an erection and problems with ejaculating
women having some vaginal bleeding
both men and women having breast swelling

Sexual side effects are not common and should pass after the first couple of weeks. If they don't, and this is a problem for you, go back to your doctor to see if there's another medicine you can try.

If you're a woman and you get vaginal bleeding after the menopause, make an appointment to see your doctor as soon as possible.

Will it affect my fertility?

Amitriptyline doesn't affect male or female fertility.

Will recreational drugs affect it?

Cannabis with amitriptyline can make you feel very sleepy, especially if you've just started taking amitriptyline. Cannabis with amitriptyline can also give you a fast heartbeat.

It can be potentially dangerous to take amitriptyline with:

methadone
stimulants like MDMA (ecstasy) or cocaine
hallucinogens like LSD
novel psychoactive substances (which used to be known as legal highs) like mephedrone

Amitriptyline hasn't been properly tested with recreational drugs. Talk to your doctor if you think you might use recreational drugs while taking amitriptyline.