Antidepressant medicines

by | Medicines, Mental Health

Antidepressants are medicines that can be prescribed to treat depression and its symptoms. Antidepressant medicines can also sometimes be used to treat other conditions, including anxiety disorders and chronic (ongoing) pain.

How do antidepressant medicines work?

Antidepressant medicines are not stimulants or ‘uppers’, they do not change your personality and they are not addictive. When antidepressants are used properly, they can be extremely effective in treating depression and helping depressed people feel like themselves again.

Antidepressant medicines are also used in the treatment of anxiety disorders (including obsessive compulsive disorder and social anxiety disorder), post-traumatic stress disorder, bulimia nervosa (an eating disorder), and sometimes in the treatment of chronic pain or nerve pain.

It is not completely understood how antidepressants work to improve the symptoms of the above conditions. However, it is clear that some of their effects are due to their influence on the levels of certain chemicals called neurotransmitters in the brain. The various types of antidepressants work in different ways to influence neurotransmitters such as serotonin, noradrenaline, melatonin and dopamine.

Who can prescribe antidepressants?

Doctors, including general practitioners (GPs) and psychiatrists (specialists in mental health) can prescribe antidepressant medicines. Psychologists specialise in psychological treatments and do not prescribe medication, but they can talk to your doctor if they believe a trial of medicine would be of benefit.

Is depression always treated with antidepressants?

Not all people with depression need to take antidepressant medicines. Mild depression can often be treated with psychological therapies and lifestyle adjustments (such as getting enough sleep, eating healthy foods and exercising). Moderate to severe depression is more likely to respond to antidepressant medicines, or a combination of medication, psychological therapy and lifestyle changes.

Factors that your doctor will consider when working out whether antidepressants may be of benefit (and which ones to prescribe) include:

  • how severe your depression is;
  • your past medical history;
  • your current medical problems and other medicines being taken;
  • whether any antidepressant medicines have worked for you in the past; and
  • the side effects you might be likely to experience.

What if I don’t want to take antidepressants?

Psychological therapy is often used together with antidepressants to treat depression. For people with mild or moderate depression, psychological treatment alone may be appropriate. Your doctor will discuss with you the most appropriate treatment for you based on your symptoms, preferences and past history.

Remember that depression is a serious illness, and without appropriate treatment it can have a serious impact on your health. In severe cases depression can be life-threatening. Antidepressants are sometimes needed to help relieve your symptoms and for you to make a full recovery.

Which antidepressant will my doctor prescribe?

There are several different types of antidepressants – which one is best for you will depend on your symptoms and diagnosis, other medicines you are taking and possible side effects. Sometimes it’s necessary to try a couple of different medicines to work out which one works best for you.

Antidepressant medicines
Medicine type/class Medicines/Brand names What they are used for Some possible side effects
Selective serotonin reuptake inhibitors (SSRIs) Citalopram (e.g. Cipramil), escitalopram (e.g. Lexapro), fluoxetine (e.g. Prozac), fluvoxamine (e.g. Luvox, Movox), paroxetine (e.g. Roxet, Paxtine), sertraline (e.g. Zoloft) Depression
Anxiety disorders such as obsessive compulsive disorder
Post-traumatic stress disorder
Sexual dysfunction (including reduced libido, or sex drive, difficulty having an orgasm, problems ejaculating), nausea, loss of appetite, diarrhoea, insomnia (difficulty sleeping)
Noradrenaline reuptake inhibitors (NARIs) Reboxetine (brand name Edronax) Depression Insomnia, tiredness, nausea, constipation
Noradrenaline and specific serotonergic antidepressants (NaSSAs); also called tetracyclic antidepressants Mirtazapine (e.g. Avanza, Axit), mianserin (Lumin, Tolvon) Major depression; depression with anxiety Tiredness, dry mouth, constipation, weight gain. Blood tests needed with mianserin, which can rarely cause a serious blood disorder
Melatonergic agonists Agomelatine (brand name Valdoxan) Major depression Tiredness, dizziness, rarely hepatitis. Blood tests are needed to check liver function.
Serotonin and noradrenaline reuptake inhibitors (SNRIs) Desvenlafaxine (e.g. Pristiq), duloxetine (e.g. Andepra, Cymbalta), venlafaxine (e.g. Efexor, Altven) Severe depression
Nerve pain
Anxiety disorders
Headache, sweating, sexual dysfunction (including reduced libido, difficulty having an orgasm, problems ejaculating), nausea, diarrhoea, reduced appetite
Reversible inhibitors of monoamine oxidase (RIMAs) Moclobemide (e.g. Aurorix, Amira) Mild-to-moderate depression with anxiety Sleep disturbances, dizziness, nausea, dry mouth, headache
Tricyclic antidepressants (TCAs) Amitriptyline (e.g. Endep, Entrip), clomipramine (e.g. Anafranil, Placil), dothiepin (Dothep), imipramine (Tofranil, Tolerade), nortriptyline (Allegron, NortriTABS), doxepin (Deptran, Sinequan) Severe depression. Can help with symptoms of anxiety
Chronic (ongoing) pain
OCD can be treated with clomipramine
Dry mouth, blurred vision, constipation, sexual dysfunction (including reduced libido, difficulty having an orgasm, problems ejaculating), weight gain, sleepiness
Monoamine oxidase inhibitors (MAOIs) Phenelzine (Nardil), tranylcypromine (Parnate) Severe or atypical depression Dry mouth, blurred vision, dizziness, constipation, sexual dysfunction, weight gain, insomnia. Risk of severe high blood pressure if certain foods or medicines taken while on this medicine
Serotonin modulators Vortioxetine (brand name Brintellix) Severe depression Nausea, vomiting, diarrhoea

Managing the unwanted side effects of antidepressants

Some side effects, such as nausea, settle after a few weeks of being on medication. Others can be helped by making small adjustments, such as the time of day you take the medicine. Let your doctor know straight away if you are experiencing side effects, as they should be able to help.

When younger people with depression first start taking antidepressants, there can be a slightly increased risk of suicidal thoughts and behaviours. Close monitoring by your doctor is important, especially during the first few weeks of treatment.

How soon will I feel better?

If you have depression, it will probably be one to 2 weeks after starting the medicine before you begin to feel better, so do not be discouraged if things do not improve straight away. It may take 6 weeks or longer for you to feel the full benefit of antidepressant treatment. Also, some of your symptoms might get better sooner than others — if you have sleeplessness, for example, this might go away before another symptom, such as your mood improves.

If you think your antidepressant medicine is not working for you, see your doctor. Your doctor may recommend increasing the dose. If there is still no improvement after a few weeks, you’ll most likely need to try a different antidepressant. To avoid interactions between the different antidepressants, you may have to wait a couple of days to 2 weeks before switching to your new antidepressant, depending on the medicines used. This is called a ‘washout’ period. Some people may need to try several different medicines and doses before they find the one that works for them.

How long will I have to take antidepressants?

If you are prescribed antidepressant medicines, it is very important that you follow your doctor’s instructions so that you have the best chance of a full recovery. Your doctor might recommend that you take antidepressants for what appears to be a long time – usually at least 6 to 12 months. You should follow this advice, and do not stop taking the medicine as soon as you begin to feel better. Your symptoms may return if you stop the medicine before your doctor recommends.

If you’ve had depression that has come back after stopping treatment in the past, your doctor may recommend staying on antidepressants for longer than 12 months. Some people find that they need to keep taking antidepressants long term to stop their symptoms returning, but many people are able to control their symptoms with lifestyle measures and psychological therapies after stopping antidepressants.

Stopping antidepressants

When it is time to stop taking antidepressants, it’s generally recommended that you gradually reduce the dose. Don’t stop taking antidepressants abruptly, because stopping suddenly can make you feel agitated and unwell. This is known as discontinuation syndrome, and can cause symptoms such as insomnia, nausea, flu-like symptoms, headache, sweating and balance problems. The symptoms are usually mild, but can be avoided by slowly reducing the dose.

Can children and teenagers take antidepressants?

Antidepressant medication is not usually the first choice of treatment for children, and is generally not recommended. There are some antidepressants that can be prescribed by child psychiatrists in certain circumstances for children and teenagers with anxiety or depression.

As with any medicine, there are risks associated with the use of antidepressant medicines. Young people (under 25 years) taking SSRIs for depression may have a slightly increased risk of suicidal thoughts and behaviour when they first start taking these medicines. Close monitoring is needed in any child, teenager or young person taking antidepressants, especially when antidepressants are first started.

Can you take antidepressants with other medicines?

Antidepressants can interact with other medicines, so you should always check with your doctor before taking any new medicines while you are on antidepressants. Interactions between medicines can cause serious health problems.

Problems can occur with prescription, over-the-counter and complementary medicines such as St John’s wort, which interacts with several antidepressants. In the case of MAOIs, there are even some foods and drinks that need to be avoided while taking these medicines.

Can I drink alcohol while taking antidepressants?

Alcohol is a depressant drug and should generally be avoided if you have depression. Alcohol should also ideally be avoided when taking most antidepressants. That’s because the combination of the sedating effects of alcohol plus the effects of the medicine can be dangerous.

Check with your doctor or pharmacist about whether there may be an interaction between the antidepressant you are taking and alcohol.

Can you take antidepressants when you are pregnant or breast feeding?

See your doctor if you are pregnant or planning a pregnancy and are taking antidepressants. It is very important that depression is not undertreated during pregnancy. Your doctor can discuss with you the risks and benefits of different antidepressants for both you and your baby.

Your doctor may recommend that you change to a different type of antidepressant, as there are some antidepressants that are preferred and others that should not be used during pregnancy or when breast feeding.