Amitriptyline is an antidepressant medicine. It's used to treat low mood and depression. It works by increasing levels of a chemical called serotonin in your brain. This can improve your mood.
Once you take amitriptyline you may start to feel better after 1 to 2 weeks. But it can take 4 to 6 weeks for amitriptyline to work fully.
Amitriptyline is only available on prescription and comes as tablets and as a liquid.
It is also used for some types of pain and to prevent migraines in lower doses.
Amitriptyline for pain and migraine
Check if you can take amitriptyline
Most adults age 18 and over can take amitriptyline. But amitriptyline is not suitable for some people.
To make sure it's safe for you, talk to your GP before taking amitriptyline if you:
- are taking any other medicines or have taken any in the last 14 days
- have ever had an allergic reaction to amitriptyline or any other medicine
- have a heart problem - amitriptyline can make some heart problems worse
- have porphyria (a rare blood disorder)
- have liver problems
- have epilepsy or are having electroconvulsive treatment (ECT) - amitriptyline may increase your risk of having a fit or seizure
- are pregnant, trying to get pregnant or breastfeeding
- have glaucoma - amitriptyline can increase the pressure in your eye
- have thoughts about harming yourself or ending your life
- have problems emptying your bladder
- have type 1 or type 2 diabetes
Diabetes and amitriptyline
If you have diabetes, amitriptyline can make it more difficult to keep your blood glucose stable.
Monitor your blood glucose more often for the first few weeks of treatment with amitriptyline and adjust your diabetes treatment if necessary.
Talk to your GP or diabetes team if you’re worried about your blood glucose levels.
Pregnancy and amitriptyline
Amitriptyline is not recommended during pregnancy. But your GP may feel that its benefits outweigh the risks for you.
It has been linked with a small risk of problems for the baby if you take it in early or late pregnancy.
Non-urgent advice: Talk to your GP before taking amitriptyline if you:
- are pregnant
- think you may be pregnant
- are trying to get pregnant
Breastfeeding and amitriptyline
Talk to your GP before taking amitriptyline if you're breastfeeding.
Amitriptyline passes into breast milk. It's been linked with side effects such as sleepiness in breastfed infants.
It's important not to share a bed with your baby while you're taking amitriptyline.
Your GP may prescribe another antidepressant you can take instead.
Fertility and amitriptyline
There's no evidence that amitriptyline affects either male or female fertility.
Contraception and amitriptyline
Amitriptyline does not affect any type of contraception, including the combined pill and emergency contraception.
How to take amitriptyline for depression
You'll usually take amitriptyline once a day. It's best to take it before bed 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.
Amitriptyline does not usually upset your stomach, so 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 do not have a syringe or the correct spoon, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not measure the right amount.
If you forget to take amitriptyline
If you forget a dose, leave out the missed dose and take your next dose as normal.
If you take amitriptyline 2 or 3 times a day and forget a dose, take it as soon as you remember unless it's close to the time for your next dose.
Never take 2 doses at the same time to make up for a forgotten dose.
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.
If you take too much amitriptyline
The amount of amitriptyline that can lead to an overdose varies from person to person.
Urgent advice: Contact your GP urgently or go to your nearest emergency department (ED) if:
- you've taken more than your prescribed dose of amitriptyline
Do this even if you feel well.
Do not drive yourself. Get someone else to drive you or call 999 or 112 for an ambulance.
Bring the amitriptyline packet or the leaflet inside it and any remaining medicine with you.
If you take too much amitriptyline you may:
- feel drowsy
- get sick (vomit)
- start shaking
- have a fast heart rate
- have fits or seizures (shaking and jerking uncontrollably)
These are only some of the possible symptoms of an overdose. Read the patient information leaflet for a full list of symptoms.
Alcohol and amitriptyline
You can drink alcohol while taking amitriptyline. But it may make you feel sleepy. Stop drinking alcohol until you see how the medicine makes you feel.
Coming off amitriptyline
Most GPs recommend that you take antidepressants for 6 months to a year after you've stopped feeling depressed. Stopping before then can make depression come back.
If your GP suggests that you come off amitriptyline, they may recommend reducing your dose gradually.
This is to help prevent any withdrawal side effects you might get as a reaction to coming off the medicine. These include:
- feeling dizzy
- feeling sick
- numbness or tingling in the hands or feet
- trouble sleeping
- feeling agitated or anxious
- headaches
- shaking
Important
Do not stop taking amitriptyline suddenly, or without talking to your GP first.
Side effects of amitriptyline
Amitriptyline can cause side effects in some people. But many people have no side effects or only minor ones.
Common side effects
Some of the common side effects of amitriptyline gradually improve as your body gets used to the medicine.
There are things you can do to help cope with them:
Constipation
Get more fibre into your diet such as fresh fruit, vegetables and cereals, and drink plenty of water. Try to exercise more regularly, for example, by going for a daily walk or run.
If this does not help, talk to your pharmacist or GP.
Feeling dizzy
This is probably due to low blood pressure. Amitriptyline can reduce your blood pressure when you stand up.
Drink plenty of water or other non-alcoholic drinks. Do not stand up too quickly after you've been sitting or lying down. Do not drive, cycle or use tools or machines if you feel dizzy.
Dry mouth
Chew sugar-free gum or suck sugar-free sweets.
Feeling sleepy or tired
Take amitriptyline before bed. Do not drink too much alcohol. Do not drive, cycle or use tools or machinery if you feel sleepy or tired.
Difficulty peeing
Relax when you try to pee. Do not try to force the flow of pee. If you cannot pee, try again a short time later.
Talk to your GP urgently if you cannot pee at all.
Headache
Speak to a GP or pharmacist if the advice on how to cope does not help and a side effect is still bothering you or does not go away.
Keep taking amitriptyline. But talk to your GP or pharmacist if these common side effects bother you or do not go away.
These are not all the side effects of amitriptyline. For a full list see the patient information leaflet inside your medicines packet.
Serious side effects
Serious side effects after taking amitriptyline are rare. But some people do have them.
Urgent advice: Contact your GP straight away if you have:
- a fast or irregular heartbeat
- yellowing of the skin or the whites of your eyes (jaundice) - this can be signs of a liver problem
- constant headaches, long-lasting confusion or weakness, frequent muscle cramps - these can be signs of low sodium levels in your blood
- bruising, bleeding or a sore throat and fever - these can be signs of a problem with your blood cells
- thoughts about harming yourself or ending your life
- eye pain, a change in your eyesight, swelling or redness in or around the eye
- you have constipation that lasts a long time
- you have problems peeing which are causing stomach pain
Emergency action required: Call 122 or 999 and ask for an ambulance if you:
- have weakness on 1 side of your body
- have trouble speaking or thinking
- lose your balance or have blurred eyesight
Serious allergic reaction
A serious allergic reaction (anaphylaxis) to amitriptyline is rare. But it can happen.
Emergency action required: Call 112 or 999 or go to an ED now if:
- you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
- you're wheezing
- you get tightness in your chest or throat
- you have trouble breathing or talking
- your mouth, face, lips, tongue or throat start swelling
- your lips, mouth, throat or tongue suddenly become swollen
Non-urgent advice: Find your patient information leaflet
Your patient information leaflet is the leaflet that comes with your medicine. You can find a digital version of the leaflet online.
Report side effects
You can report any suspected side effects to the Health Products Regulatory Authority (HPRA): report an issue - hpra.ie
Taking amitriptyline with other medicines
Some medicines interfere with amitriptyline and can increase the chance of you having side effects. This includes herbal remedies, vitamins or supplements.
Tell your GP or pharmacist that you are taking amitriptyline before starting any new medicine.
Taking amitriptyline with opioid medicines can increase your risk of becoming very drowsy and having breathing problems.
Opioid medicines include:
- codeine
- morphine
- dihydrocodeine
- buprenorphine
- fentanyl
- oxycodone
Tell your GP if you have ever taken any other medicines for depression. Some antidepressants can affect the way amitriptyline works and cause very high blood pressure. This can happen even after you stop taking them.
Tell your doctor or dentist that you are taking amitriptyline if you are going to have a general or local anaesthetic as part of surgery or dental treatment.
Amitriptyline and herbal remedies and supplements
Do not take St John's wort, a herbal remedy for depression, while you're taking amitriptyline. It can increase your risk of side effects.
There's not enough information about taking amitriptyline with other herbal remedies and supplements. They are not tested in the same way as medicines.
Tell your GP or pharmacist if you're taking any other medicines, including herbal medicines, vitamins or supplements.