Researchers from Imperial College London are looking for volunteers to test whether cannabinoids, the active ingredient of cannabis, can be used to alleviate the sensation of breathlessness caused by illnesses such as chronic obstructive pulmonary disease (COPD).
The team are looking for volunteers aged between 50 and 70, who don't have breathing difficulties.
Dr Elspeth Pickering, clinical research fellow, from Imperial College London and Chelsea and Westminster Hospital, says: "Despite the best efforts of scientists for many years, no one has been able to develop a way to deal with the sensation of breathlessness without suppressing the drive to breathe. Breathlessness can have a major impact on the quality of life for patients with respiratory diseases, and by using a cannabinoid, we hope to find a way to block the mechanism which causes it."
The researchers believe the cannabinoids could be used to reduce the sensation of breathlessness without depressing the respiratory system.
The study will take a morning on two different days, during which time volunteers will be hooked up to a circuit to regulate and measure their breathing. Carbon dioxide will be added to the air breathed by the volunteers, causing the sensation of breathlessness. This is a safe method of simulating breathlessness as the body naturally produces carbon dioxide.
Afterwards the volunteers will be given a spray which includes tetrahydrocannabinol (THC), the active ingredient in cannabis, which researchers hope will reduce the sensation of breathlessness.
Dr Anita Holdcroft from Imperial College London and Chelsea and Westminster Hospital, and study leader, adds: "The special formulation of the drug as a spray avoids the harmful effects of smoking cannabis. We hope the drug will stop the sensation of breathlessness, potentially providing a new way to deal with respiratory diseases."
The study will be conducted at Charing Cross Hospital in west London. Volunteers will be paid for their time committed to the study. Volunteers aged between 50 and 70 who don't have breathing difficulties and wish to take part should call 020 8846 1234 ext. 7055 to register their interest.