Little evidence that antidepressants work for chronic pain

There is very little scientific proof that being prescribed antidepressants will help people with long-term chronic pain, a study has suggested, with researchers bemoaning the ‘shocking’ lack of hard evidence in this area.

The Cochrane review, led by scientists from several UK universities, including Southampton and Newcastle, examined 176 trials, including studying drugs such as Prozac and the antidepressant amitriptylin.

It concluded that there is, at best, only ‘moderate’ evidence for one drug helping, duloxetine, and even then only for short-term pain relief. Another drug, mirtazapine, had a moderate effect on mood and duloxetine, again, a small effect, it added. However, the study cautioned that it mostly looked at patients’ experience over a couple of months only.

The study raises questions about recommendations from the National Institute for Health and Care Excellence (NICE), which in 2020 suggested that a range of commonly used painkillers for chronic pain, including paracetamol, could do more harm than good. It recommended instead that some antidepressants should be considered for people with chronic primary pain

For the latest study, the University of Southampton’s Professor Tamar Pincus said: “It’s really shocking that we don’t have any evidence for long-term use of even duloxetine.

“This is a global public-health concern. Chronic pain is a problem for millions who are prescribed antidepressants without sufficient scientific proof they help, nor an understanding of the long-term impact on health,” she added.

However, Prof Pincus emphasised that the study’s findings did not mean patients should stop taking medication they have already been prescribed. “It does not mean that people should stop taking prescribed medication without consulting their GP,” she said.

NHS guidance, for example, recommends that, when coming off antidepressants, medication should be slowly reduced over weeks to prevent withdrawal symptoms.

Clinical lead for NICE’s chronic-pain guidelines Dr Cathy Stannard added: “This well-conducted review adds to the substantial evidence we now have that shows that the use of medicines to treat long-term pain is disappointing.”

However, it could be difficult to translate results from clinical trials to real life. “It’s equally important to emphasise the many social and psychological influences on the pain experience,” Dr Stannard said.

“Existing services, usually outside healthcare, including support with mobility, debt management, trauma, and social isolation, can be helpful for people living with pain – and identifying what matters most to people and signposting to appropriate local support is a promising way forward,” she said.

Separately, a survey by the BBC of more than 4,000 adults has concluded a quarter (26%) are living with long-term pain. Of these 24% were taking opioid painkillers and 23% were stuck on NHS waiting lists for either surgery or a pain management programme.