Tricyclic antidepressants are used to treat depression and some other conditions. They often take 2-4 weeks to work fully. A normal course of antidepressants lasts at least six months after symptoms have eased. Side-effects may occur but are often minor and may ease off. At the end of a course of treatment, you should gradually reduce the dose before stopping completely.
Tricyclic antidepressants are not just for depression
Tricyclic antidepressants are used to treat depression. They are also used to treat some other conditions such as migraine, panic disorder, obsessive-compulsive disorder, recurrent headaches, and some forms of pain. The word tricyclic refers to the chemical structure of the medicine.
How do antidepressants work?
Antidepressants alter the balance of some chemicals in the brain, called neurotransmitters. An imbalance of the neurotransmitters is thought to play a part in causing depression and other conditions. Tricyclic antidepressants generally block the effects of two neurotransmitters called serotonin and noradrenaline (norepinephrine). The role these chemicals have in causing, or treating, depression is unclear.
How effective are tricyclic antidepressants?
About 5-7 in 10 people with moderate or severe depression have an improvement in symptoms within a few weeks of starting treatment with an antidepressant. However, up to 3 in 10 people improve with dummy tablets (placebos), as some people would have improved in this time naturally. So, if you have depression, you are roughly twice as likely to improve with an antidepressant compared with taking no treatment. However,, they do not work in everybody. As a rule, the more severe the depression, the greater the chance that an antidepressant will work well.
Note: antidepressants do not necessarily make sad people happy. The word 'depressed' is often used when people really mean sad, fed up, or unhappy. True depression is different to unhappiness and has persistent symptoms (which often include persistent sadness). See separate leaflet called Depression for more details.
How quickly do tricyclic antidepressants work?
Some people notice an improvement within a few days of starting treatment. However, an antidepressant often takes 2-4 weeks to build up its effect and work fully. Some people stop treatment after a week or so thinking it is not helping. It is best to wait for 3-4 weeks before deciding if an antidepressant is helping or not. If poor sleep is a symptom of the depression, it is often helped first, within a week or so.
With some types of tricyclic antidepressant, the initial dose that is started is often small and is increased gradually to a full dose. (One problem that sometimes occurs is that some people remain on the initial dose which is often too low to work fully.)
If you find that the treatment is helpful after 3-4 weeks, it is usual to continue. A normal course of antidepressants lasts at least six months after symptoms have eased. If you stop the medicine too soon, your symptoms may rapidly return. Some people with recurrent depression are advised to take longer courses of treatment (up to two years or longer).
When you are taking tricyclic antidepressants
It is important to take the medication each day at the dose prescribed. Do not stop taking it abruptly. This is because you may develop some withdrawal symptoms. The dose is usually gradually reduced before stopping completely at the end of a course of treatment. But don't do this yourself - your doctor will advise on dosage reduction when the time comes. It is best not to stop treatment or change the dose without consulting a doctor.
Are there different types of tricyclic antidepressants?
There is no best type that suits everyone. A doctor makes a judgement as to which one would best suit, taking into account things such as:
- Your age.
- Other medicines that you may take.
- Other medical problems.
- Possible side-effects.
- Previous use of antidepressants.
If the one chosen does not suit, it is sometimes necessary to change the dose, or change the preparation. Also, if tricyclic antidepressants do not help then another type of antidepressant may be advised.
What about side-effects and risks?
Most people have either minor, or no, side-effects. Possible side-effects vary between different preparations. The leaflet that comes in the medicine packet gives a full list of possible side-effects. You should read this before you start taking the medicine. It is beyond the scope of this leaflet to list all side-effects; however, the following highlights some of the more common or serious ones. As a rule, tell your doctor if a side-effect persists or is troublesome. Your doctor can advise on the best course of action - for example, to stop the medication, a switch to a different drug, etc.
The most common side-effects
These include a dry mouth, constipation, sweating, slight hesitancy in passing urine and slight blurring of vision. It is worth keeping on with treatment if these side-effects are mild at first. Minor side-effects may wear off after a week or so. Frequent drinks of water will help a dry mouth. Also, some people find that sucking pineapple chunks helps with the flow of saliva and helps to ease the feeling of dry mouth.
A possible sedating effect
Tricyclic antidepressants can cause drowsiness (a sedating effect) in some people. You must be aware of this possibility, especially if you are a driver, as it may impair your ability to drive safely. Any sedating effect is likely to be greatest in the first month of starting treatment, or on increasing the dose. The Driver and Vehicle Licensing Agency (DVLA) advises that you should not drive during this time if you feel that you are drowsy or sedated at all. Also, do not operate machinery if you feel drowsy.
Small increased risk of fractures
Research studies suggest that there is a small increased risk of fractures in people taking tricyclic antidepressants. However, the reason for this increased risk is not clear.
Antidepressants and suicidal behaviour
In recent years there have been some case reports which claim a link between taking antidepressants and feeling suicidal, particularly in teenagers and young adults. This may be more of a risk in the first few weeks of starting medication or after a dose increase. It is debatable whether this possible risk is due to the medicine or to the depression. If it is due to the medication then the risk remains very small. And, overall, the most effective way to prevent suicidal thoughts and acts is to treat depression. However, because of this possible link, see your doctor promptly if you become increasingly restless, anxious or agitated, or if you have any suicidal thoughts. In particular, if these develop in the early stages of treatment or following an increase in dose.
Problems with sexual function are a common symptom of depression. However, in addition to this, all antidepressants may cause some problems with sexual function. For example, decreased sex drive (libido), difficulty getting an erection, delayed orgasm, and impaired ejaculation have been reported as side-effects in some people taking tricyclic antidepressants.
Are antidepressants addictive?
Tricyclic antidepressants are not tranquillisers and are not thought to be addictive. Most people can stop tricyclic antidepressants without any problem. At the end of a course of treatment it is usual to reduce the dose gradually over about four weeks before finally stopping. This is because some people develop withdrawal symptoms if an antidepressant is stopped abruptly. If you have withdrawal symptoms it does not mean that you are addicted to the medicine, as other features of addiction, such as cravings for the medicine, do not occur.
Withdrawal symptoms that may occur include:
- Anxiety and agitation
- Sleep disturbance
- Flu-like symptoms
- Tummy (abdominal) cramps
- Pins and needles
- Mood swings
- Feeling sick (nauseated)
- Low mood
These symptoms are unlikely to occur if you reduce the dose gradually. If withdrawal symptoms do occur, they will usually last less than two weeks. An option if they do occur is to restart the medicine and reduce the dose even more slowly.
How to use the Yellow Card Scheme
If you think you have had a side-effect to one of your medicines you can report this on the Yellow Card Scheme. You can do this online at the following web address: www.mhra.gov.uk/yellowcard.
The Yellow Card Scheme is used to make pharmacists, doctors and nurses aware of any new side-effects that medicines or any other healthcare products may have caused. If you wish to report a side-effect, you will need to provide basic information about:
- The side-effect.
- The name of the medicine which you think caused it.
- The person who had the side-effect.
- Your contact details as the reporter of the side-effect.
It is helpful if you have your medication - and/or the leaflet that came with it - with you while you fill out the report.
Further help & information
15-19 Broadway, London, E15 4BQ
Tel: (Infoline) 0300 123 3393, (General) 020 8519 2122
Further reading & references
- Depression in adults: recognition and management; NICE Clinical Guideline (April 2016)
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but makes no warranty as to its accuracy. Consult a doctor or other healthcare professional for diagnosis and treatment of medical conditions. For details see our conditions.
Dr Tim Kenny
Dr Gurvinder Rull
Dr Laurence Knott