What does this rating mean?
Antidepressants are medications designed to treat depression. They can only be prescribed by a doctor. Some antidepressants are also used to treat psychological disorders other than depression, including anxiety.
There are several different classes (types) of antidepressants. Each of these classes includes several different drugs. The main classes of antidepressants are listed below, along with common medications (the chemical name) and their brand names (the label they are sold under).
The tricyclics and the MAOIs are older classes of antidepressants, with the MAOIs seldom used these days. SSRIs are the most commonly prescribed type of antidepressant at the moment.
Antidepressants work by changing the level of neurotransmitters (chemical messengers) in the brain. Several neurotransmitters are thought to be in low supply in depression, including noradrenaline (sometimes called norepinephrine) and serotonin. It is thought that increasing the levels of these neurotransmitters can be helpful in depression.
Tricyclics mainly increase the level of noradrenaline in the brain. The SSRIs work by increasing the supply of serotonin only. The SNRIs and RIMAs increase the supply of both serotonin and noradrenaline in the brain. MAOIs increase the availability of both serotonin and dopamine.
Some newer types of antidepressants work in different ways.
Most antidepressants need to be taken for at least 6 to 9 months after symptoms disappear. Stopping an antidepressant too early increases the chances of depression symptoms returning.
There are a very large number of studies showing that antidepressants work better than placebos (dummy pills) for adults with moderate to severe depression. Tricyclic antidepressants, SSRIs and RIMAs work equally well. The best effects come from combining an antidepressant with a psychological therapy, such as cognitive behaviour therapy.
Some people may not respond to the first antidepressant they are prescribed (i.e. it does not reduce their depression symptoms). However, they may respond well to another antidepressant of the same type, or one of a different type.
Tricyclics do not appear to work for children and have only limited effects on adolescents. There is some evidence that the SSRI fluoxetine is effective in children and adolescents. However, other SSRIs are not advised in children and adolescents because of safety concerns.
Click each section below to read more about the potential disadvantages of antidepressants.
Antidepressants can be prescribed by a doctor, including GPs and psychiatrists.
Antidepressants are one of the best treatments available for depressed adults, but caution is advised for children and adolescents. For adults, antidepressants can be combined with a psychological treatment for even better results.
Last reviewed and updated: 20 December 2023