The Royal Victoria Hospital is looking for patients to test if cannabis can act as a superior form of pain relief.
Patients facing surgery at the hospital are invited to apply to participate in the study run by the British Medical Research Council at 20 hospitals in the UK, including the Royal in Belfast.
"No, we will not be offering patients joints after their operations," said a spokeswoman for the council yesterday. The study would be strictly controlled and the cannabis would be taken in tablet form, she explained.
She said, however, that the oral form of cannabis could induce feelings of euphoria in the patient but added that a placebo and a paracetamol-based pain relief tablet, which would be part of the trial also, could have a similar effect.
If found to be effective and without adverse side effects the oral cannabis plant extract could provide another pain relief option to doctors and patients, the council said.
There is already some anecdotal evidence that suggests cannabis could be effective at relieving pain for a variety of debilitating conditions, said the council. "Administering drugs to alleviate post-operative pain is a routine procedure in hospitals, and this provides a useful way to measure the effects of cannabis against other pain-relieving drugs," it added.
The researchers have been working to establish an appropriate dose of the cannabis extract. Now they must rigorously compare the pain relief derived from it against a standard oral drug for pain relief administered after an operation.
The £500,000 trial is led by Dr Anita Holdcroft from Imperial College London, at the Chelsea and Westminster Hospital. The trial wants to recruit 400 surgical patients across the UK to take part in the study.
Consultant anaesthetist Prof Rajinder Mirakhur is running the trial in Belfast. He was not available for comment yesterday but Dr Holdcroft said: "We need to assess the scientific merits of some of the anecdotal evidence and we need to do this in the same way as any other experimental pain treatment. This is a proper study in a clinical setting where patients can be routinely monitored, using an oral capsule containing a prescribed dose."
Patients will be randomly assigned to one of four oral treatments containing either standardised cannabis extract, a synthetic form of cannabis called tetrahydrocannabinol (an active ingredient in cannabis), a standard pain relieving drug, or a placebo.
Pain relief and side effects will be assessed over a six-hour period.
Patients will be asked by a researcher to respond to questions about their pain and general feelings, such as sickness, every half to one hour while they are awake. Patients can request additional pain relief at any time.
After six hours of study, volunteers may receive a choice of standard pain medications: either another oral drug or an alternative form of pain medication.
