British scientists have created a potential new treatment for depression by combining a medication for pain relief with one for combating addiction.

Current antidepressants, called SSRIs, increase the level of serotonin in the brain, although the exact mechanism by which they work is unclear.

Outlook: Researchers in the UK have discovered what they believe to be a new treatment for depression.

Between 30 and 50 per cent of patients do not respond to the treatment, which can take several weeks to work and cause significant side effects, researchers say.

A team at the University of Bath have combined buprenorphine, a painkiller used post-surgery, and naltrexone, a drug used for treating addiction.