Most antidepressants used for chronic pain are being prescribed with “insufficient” evidence of their effectiveness, scientists have warned.

The Cochrane review, led by scientists from several UK universities including Newcastle and Southampton, examined 176 trials consisting of nearly 30,000 patients involved in assessments which prescribed antidepressants for chronic pain.

Among the drugs studied were amitriptyline, fluoxetine, citalopram, paroxetine, sertraline, and duloxetine – with only the latter showing reliable evidence for pain relief. Amitriptyline is one of the most commonly prescribed antidepressants for pain management worldwide. In the last 12 months, around 10 million prescriptions were given to patients in England at the 10mg dose recommended for pain.

The review has found that there is no reliable evidence for the long-term efficacy of any antidepressant, and no reliable evidence for their safety for chronic pain at any point. The researchers say the clinical evidence is not good enough to know whether medications work or not for pain. The only antidepressant the review was certain about for the treatment of chronic pain is duloxetine. Duloxetine was moderately effective across all outcomes at the standard dose.

The team found that many of the trials involved a very small number of patients making the numbers unreliable. There is currently no reliable evidence for the long‐term efficacy of any antidepressant, and no reliable evidence for the safety of antidepressants for chronic pain at any time point.

The report has also found that there is no reliable evidence on the safety of taking anti-depressants for chronic pain both short term and long term and adopting a person‐centred approach is critical. 

However, pain is a very individual experience and certain medications may work for people even while the research evidence is inconclusive or unavailable. This research further supports our view that medication, while not entirely dismissed, should no longer be a prime consideration in isolation, and a more holistic approach is required, emphasizing the psychological influences on how people experience pain, and rehabilitation which includes support such as Cognitive Behavioural Therapy and physical therapy aimed at improving mobility.

This analysis is further supported by Warwick University study funded by the National Institute for Health and Care Research, on a new treatment which can help people to reduce reliance on opioid painkillers to manage chronic pain. This has found that one in five people with chronic pain can be weaned off opioids via a programme including mindfulness, stress management and posture and movement advice. The study found that opioids can be gradually reduced without any actual worsening of pain.

This article was co-authored by Partner, Tim Large, and Senior Associate, Paul Charter.

For further commentary on chronic pain by Tim Large click here.