Key messages
– Antidepressants are more effective than placebo (pretend tablet) at improving treatment response and have similar acceptability to placebo. Fewer participants dropped out due to a lack of effectiveness in the antidepressant group compared to the placebo group and more participants dropped out due to unwanted effects in the antidepressant group compared to placebo.
– Future studies may be more transparent with their methods and outcome reporting. Future reviews may also include people with co-occurring medical conditions (comorbidities).
What is generalised anxiety disorder?
Generalised anxiety disorder is a mental health condition characterised by excessive anxiety and ongoing worry about everyday events. Generalised anxiety disorder is common and generally affects women twice as often as men.
How is generalised anxiety disorder treated?
Treatments include various psychological approaches (which work on the mind and a person's behaviour) and medicines. Among the medicines, antidepressants (which are used to treat depression), in particular, two types of antidepressants called selective serotonin reuptake inhibitors and serotonin-noradrenaline reuptake inhibitors, are commonly used for the treatment of generalised anxiety disorder and many studies have shown their benefit over a sham treatment (known as placebo).
Who will be interested in this review?
People with generalised anxiety disorder, general practitioners, and mental health professionals.
What did we want to find out?
This review aimed to provide an updated summary of all the evidence available on this topic. In particular, we wanted to find out:
– how effective antidepressants are compared to placebo in treating generalised anxiety disorder;
– how acceptable antidepressants are compared to placebo in treating generalised anxiety disorder; and
– how many unintended and harmful effects antidepressants have compared to placebo in people with generalised anxiety disorder.
What did we do?
We searched for studies that compared antidepressants to placebo for treating adults with generalised anxiety disorder but no other serious co-occurring medical conditions.
What did we find?
We found 37 studies that involved 12,226 adults with generalised anxiety disorder. The studies lasted between four and 28 weeks.
Antidepressants were more effective than placebo in reducing anxiety and there was no difference between antidepressants and placebo in the total number of people leaving the studies early.
Fewer people in the antidepressant group dropped out of the studies early due to the antidepressant being considered ineffective compared to placebo and more people in the antidepressant group dropped out of the studies early because of unwanted effects compared to placebo.
What are the limitations of the evidence?
We are confident in our findings as they apply to people with generalised anxiety disorder but without other co-occurring medical conditions. However, the evidence is not strong enough to create a clinical guideline for people with other co-occurring medical conditions as they were excluded from our analyses.
How up to date is this evidence?
The evidence is up to date to October 2022.