How do anti-depressants work
Answers
Antidepressants
Contents
Overview
Uses
Cautions
Dosage
Side effects
Alternatives
Antidepressants are a type of medicine used to treat clinical depression.
They can also be used to treat a number of other conditions, including:
obsessive compulsive disorder (OCD)
generalised anxiety disorder
post-traumatic stress disorder (PTSD)
Antidepressants are also sometimes used to treat people with long-term (chronic) pain.
Read more about when antidepressants are used.
How antidepressants work
It's not known exactly how antidepressants work.
It's thought they work by increasing levels of chemicals in the brain called neurotransmitters. Certain neurotransmitters, such as serotonin and noradrenaline, are linked to mood and emotion.
Neurotransmitters may also affect pain signals sent by nerves, which may explain why some antidepressants can help relieve long-term pain.
While antidepressants can treat the symptoms of depression, they don't always address its causes. This is why they're usually used in combination with therapy to treat more severe depression or other mental health conditions.
How effective are antidepressants?
Research suggests that antidepressants can be helpful for people with moderate or severe depression.
Studies have shown that they’re better than placebo ("dummy medicine") for people with these conditions.
They're not usually recommended for mild depression, unless other treatments like therapy haven't helped.
The Royal College of Psychiatrists estimates that 50 to 65% of people treated with an antidepressant for depression will see an improvement, compared to 25 to 30% of those taking a placebo.
Doses and duration of treatment
Antidepressants are usually taken in tablet form. When they're prescribed, you'll start on the lowest possible dose thought necessary to improve your symptoms.
Antidepressants usually need to be taken for 1 or 2 weeks (without missing a dose) before the benefit starts to be felt. It's important not to stop taking them if you get some mild side effects early on, as these effects usually wear off quickly.
If you take an antidepressant for 4 weeks without feeling any benefit, speak to your GP or mental health specialist. They may recommend increasing your dose or trying a different medicine.
A course of treatment usually lasts at least 6 months. Some people with recurrent depression may be advised to take them indefinitely.