Amitriptyline for pain and migraine - OLD
NHS medicines information on amitriptyline for pain - how it works, side effects, dosage and who can take it.
About amitriptyline for pain and migraine
Amitriptyline is a medicine used for treating pain. You can take it:
- to treat nerve pain (neuralgia) and back pain
- to help prevent migraine attacks
Amitriptyline is available on prescription. It comes as tablets and as a liquid that you drink.
Amitriptyline is also used to treat depression.
Read about amitriptyline for depression.
Key facts
- It's best to take your amitriptyline in the evening or before you go to bed. This is because it can make you feel sleepy.
- You may start to feel better after 1 or 2 weeks, 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 want to stop taking it.
- Amitriptyline is also used to treat depression, but at lower doses it's very good for treating pain.
Who can and cannot take amitriptyline
Most adults (aged 18 and over) can take amitriptyline. Children aged 2 years and older can take it for some types of nerve pain.
Amitriptyline is not suitable for some people. Check with your doctor before starting to take amitriptyline if you:
- have ever had an allergic reaction to amitriptyline or any other medicine
- have a heart problem – amitriptyline can make some heart problems worse
- have a rare blood disorder called porphyria
- have liver or kidney problems
- have epilepsy – amitriptyline can increase seizures or fits
- have ever taken any medicines for depression – some antidepressants used rarely can affect the way amitriptyline works
- are pregnant, trying to become pregnant, or breastfeeding
- have an eye problem called glaucoma – amitriptyline can increase the pressure in your eye
- have thoughts about harming yourself or ending your life
- have type 1 or type 2 diabetes
If you have diabetes, amitriptyline may change your blood sugar level. If you usually test your blood sugar levels, you may have to do this more often for the first few weeks of treatment. Talk to your diabetes doctor if the reading goes too high or low.
How and when to take amitriptyline
It's usual to take amitriptyline once a day. It's best to take it 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 does not usually upset your stomach. You can take it with or without food.
Swallow the tablets whole, with a drink of water. If you chew them, they taste bitter.
The liquid comes with a plastic syringe or spoon to help you measure out the right dose. If you don't have one, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not give the right amount.
Dosage
Amitriptyline tablets come in 3 different strengths – 10mg, 25mg or 50mg.
The liquid also comes in 3 different strengths – containing 10mg, 25mg or 50mg of amitriptyline in a 5ml spoonful.
The usual starting dose for adults and older children (aged 12 to 17 years) is 10mg a day. This dose can be increased by your doctor if you need better pain relief.
The starting dose for younger children depends on their weight and symptoms. The doctor will tell you how much to give them.
The maximum dose of amitriptyline for treating pain is 75mg a day. Your doctor may give you a higher dose if you're taking it to prevent migraine.
What if I forget to take it?
If you forget to take your amitriptyline, 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 one as normal.
If amitriptyline usually makes you sleepy and you need to drive, cycle or use tools or machinery, skip the missed dose and then take 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 I take too much?
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 the medicine.
Common side effects
Doses of amitriptyline for pain are lower than the doses for depression. This means 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 do not 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 have:
- 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, or get muscle cramps – 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 your eye
Reporting side effects
You can report any suspected side effect using the Yellow Card safety scheme.
Visit the Yellow Card website for more information about reporting side effects.
How to cope with side effects of amitriptyline
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 other non-alcoholic drinks every day. If you can, it may also help to do some exercise.
- dizziness – this is probably due to low blood pressure. Drink plenty of water or other non-alcoholic drinks. Do not stand up too quickly after you have been sitting or lying down.
- dry mouth – try sugar-free gum or sugar-free sweets.
- feeling sleepy or tired – take amitriptyline in the evening and cut down on the amount of alcohol you drink. Do not drive, cycle or use tools or machinery if you're feeling this way.
- difficulty peeing – relax when you try to pee. Do not try to force the flow of urine. If you still cannot go, try again later. Talk to your doctor urgently if you cannot pee at all.
- headaches – make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Try taking paracetamol or ibuprofen if you need pain relief. 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. This is because it has been linked to a small risk of problems for your 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.
Your doctor will only prescribe amitriptyline for your pain while you're pregnant if the benefits of taking the medicine outweigh the risks.
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 breastfed babies.
Talk to your doctor if you want to breastfeed. There may be other medicines that you can take instead of amitriptyline.
For more information about how this medicine can affect you and your baby during pregnancy, read this leaflet about amitriptyline on the Best Use of Medicines in Pregnancy (BUMPs) website.
You can also read more about paracetamol in pregnancy on the NHS website.
Cautions with other medicines
Many medicines and amitriptyline can affect each other and increase the chances of side effects.
Always check with your doctor or a pharmacist before starting any new medicine while you are taking amitriptyline.
Taking opioid-based medicines, like codeine, morphine or oxycodone, together with amitriptyline can increase your risk of becoming very drowsy and having breathing problems.
Tell your doctor if you have ever taken any medicines for depression. Some antidepressants can affect the way amitriptyline works to cause very high blood pressure. This can happen even after you have stopped taking them.
Mixing amitriptyline with herbal remedies and supplements
Do not take St John's wort, a herbal remedy often taken for depression, while you are being treated with amitriptyline. It will increase your risk of side effects.
There’s very little information about taking amitriptyline with other herbal remedies and supplements. They are not tested in the same way as medicines.
