Everybody feels sad or down every now and then. Sometimes these feelings can last weeks, months or even years. This could be depression – a serious illness which affects both physical and mental health.
There are 3 main types of treatment for depression:
- lifestyle changes, such as reducing any substance abuse, regular exercise, healthy sleep habits, a healthy diet, improving work-life balance, the support of family and friends, a support group, relaxation and meditation, and more
- psychological treatments
- medication, including antidepressant medicines
This page relates only to antidepressants.
What are antidepressants?
Antidepressants are medicines used to treat depression, anxiety and related conditions, such as eating disorders, obsessive-compulsive disorder and post-traumatic stress disorder.
Anybody who takes antidepressants should see their doctor regularly.
Antidepressants are effective for moderate to severe depression, but not particularly effective for mild depression. Lifestyle changes and psychological treatments work better for mild depression.
Antidepressants may be used alone, but are usually more effective when used with psychological therapies such as cognitive behaviour therapy or interpersonal therapy.
The decision to start an antidepressant should be made only in consultation with a doctor.
How do antidepressants work?
Antidepressants affect a number of chemicals in the brain which are involved with emotions and motivation.
Are there different types of antidepressants?
There are many different types of antidepressants. They can be grouped according to how they work. Within each group, there are several different medicines which work in a similar way.
The group most commonly used are the SSRIs, or selective serotonin reuptake inhibitors. They are not necessarily more effective than others, but they tend to have fewer side effects.
Other types of antidepressants are:
- SNRIs: serotonin and noradrenaline reuptake inhibitors
- Serotonin modulator
- Noradrenaline reuptake inhibitors
- TCAs (Tricyclic antidepressants)
- RIMAs (Reversible inhibitors of monoamine oxidase A)
- Tetracyclic antidepressants
- Tetracyclic analogues of mianserin
- MAOIs (monoamine oxidase inhibitors)
- Melatonergic antidepressants
There are different types of depression and anxiety, and doctors favour certain types of antidepressants for certain symptoms or disorders. As well, people respond differently to different antidepressants. It may be necessary for a doctor to trial more than one antidepressant to find one that works well with few side-effects.
NPS MedicineWise has a detailed list of antidepressants, which can be searched by active ingredient as well as by brand name.
What side-effects do antidepressants have?
All antidepressants can have side-effects, although most people have side-effects that are not bad enough that they need to stop taking the medication. The most common side-effects are headache, nausea, tiredness and sexual problems. Often, these side-effects last only a short time.
It’s important to keep the doctor informed about any side effects that may occur. It may be possible to reduce side effects by changing the dose or the time of day the medicine is taken. Some people may need to switch to another antidepressant due to side effects. You can read this factsheet from SANE Australia for a list of common side effects.
Clinical trials have found that the rates of particular side effects differ between different antidepressants. NPS MedicineWise has a list of things you should know before you take antidepressants.
Many antidepressants can interact with other medicines. Anybody taking antidepressants needs to make sure their doctor and pharmacist know what other medicines they are taking, including any complementary or alternative therapies.
There are also concerns about young people taking antidepressants. There are links between antidepressants and suicidal thoughts and behaviours in young people. But sometimes the need for antidepressants is great, and outweighs the risk of taking the medicines. The decision to prescribe antidepressants for young people is one that should be taken with great care.
How long do they take to work?
Many people will start to feel better within 2 to 4 weeks after starting an antidepressant, but it can take up to 8 weeks or longer for full effectiveness. In some people, they are not effective, no matter how long they are taken for.
Anybody who takes antidepressants should see their doctor regularly, especially in the first few weeks.
How long should I be on antidepressants?
Most people are advised to keep taking their antidepressant for at least 6 to 12 months after they start to feel better, to reduce the risk of symptoms returning. It’s important to discuss with your doctor about the best time to stop an antidepressant.
In some people, ongoing antidepressant treatment is recommended to maintain long-term control over their illness.
How do I stop taking antidepressants?
Slowly, and under a doctor’s supervision.
Stopping most antidepressants suddenly can result in unpleasant symptoms such as dizziness, nausea or feeling edgy.
It’s important to work closely with a doctor to lower the dose, stop or switch antidepressant medicines.
Are antidepressants addictive?
Antidepressants are not addictive, however it’s important to talk to a doctor before stopping them to avoid unpleasant side effects.
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Last reviewed: October 2019