Sertraline is one of the most widely prescribed medicines for depression and anxiety. It belongs to a group of drugs called selective serotonin reuptake inhibitors, or SSRIs, which work by increasing the amount of serotonin available in the brain.
Many people are told that these medicines can take several weeks before they begin to help, but new research suggests that some benefits may appear much sooner.
Scientists at University College London took a fresh look at how sertraline affects individual symptoms of depression and anxiety. Instead of only measuring whether people felt better overall, they examined how specific symptoms changed over time. This gave them a clearer picture of when the medicine starts to work.
The researchers analyzed information from the PANDA clinical trial, a large study that first reported its main results in 2019.
The original trial found that sertraline improved anxiety and general mental health after about six weeks, while improvements in depression became more obvious after 12 weeks. The new analysis used a more detailed method to examine individual symptoms one by one.
The study included 571 adults with mild to moderate depression who had complete symptom records. Participants were randomly given either sertraline or a placebo for 12 weeks. This type of study design helps researchers compare the true effects of a medicine.
The new results showed that several emotional symptoms began to improve after only two weeks of treatment. These included low mood, feelings of self-blame, restlessness, anxiety, and even suicidal thoughts. The findings suggest that some important emotional changes may happen much earlier than doctors previously believed.
Like many medicines, sertraline also caused side effects in some people. The most common included reduced appetite, tiredness, lower sex drive, and trouble sleeping. Because some of these problems can also be symptoms of depression, it can sometimes be difficult to tell whether they are caused by the illness or the medication.
The researchers found that many of these side effects became more stable after about six weeks, while the emotional benefits continued to grow. This may reassure patients who experience temporary side effects early in treatment. However, people should never stop taking antidepressants without first speaking with their doctor.
The team said depression affects people in different ways, with each person having a unique mix of symptoms. Looking at individual symptoms instead of treating depression as a single condition may help doctors choose better treatments and explain to patients what improvements they might notice first.
The findings could also help people stay hopeful during the first weeks of treatment. Seeing early improvements in mood or anxiety may encourage patients to continue taking their medicine while waiting for broader benefits to develop. More research will help confirm these results and improve personalized care.
The study was led by Dr. Giulia Piazza and colleagues at University College London and published in the journal Nature Mental Health. The findings provide new evidence that sertraline may begin relieving some important symptoms of depression and anxiety much sooner than previously thought.
If you care about mental health, please read studies about 6 foods you can eat to improve mental health, and B vitamins could help prevent depression and anxiety.
For more health information, please see recent studies about how dairy foods may influence depression risk, and results showing Omega-3 fats may help reduce depression.
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