VOLUNTEERS at a North-East hospital have been testing a cannabis-based medication for multiple sclerosis.

The 21 guinea pigs were given up to five gel-filled capsules a day containing either cannabis extract, a synthetic version of cannabis or a dummy preparation.

Patients who took part in the trials, at the Royal Victoria Infirmary, in Newcastle, found an improvement in their condition, although there were mixed results.

Last year, the Committee on Safety of Medicines (CSM) refused a licence for a cannabis-derived mouth spray.

But Professor Mike Barnes, chairman of the Royal College of Physicians' rehabilitation committee and trustee of the MS Trust, said: "My opinion is that the clinical trials show that this spray offers sustained benefit to many patients with spasticity due to MS, who are otherwise unable to find relief.

"I hope the CSM will reconsider their position and give some thought to the impact that this decision will have on the lives of those with painful, chronic disease."

Over a period of 15 weeks, doctors measured the volunteers' muscle stiffness, spasticity, pain levels and bladder control to see if the drug relieved their symptoms.

The main findings, published in The Lancet, were that neither of the cannabis-derived treatments had a significant effect on muscle spasticity.

The patients did report improvements in pain, sleep quality, spasms and spasticity, although nothing was recorded for other symptoms, such as irritability, depression, tiredness, tremors or energy levels.

In walking tests, better results were achieved by patients receiving the active cannabis treatment and, in general, the medications were well-tolerated.

Researchers concluded that while cannabinoids (extracts of cannabis) may be useful in treating some MS-related symptoms, further research is needed.

The trial, which involved patients at Newcastle and other hospitals, was funded by the Medical Research Council.