The practice is discouraged by major medical groups, considered unethical by many doctors and with uncertain benefit, but one in five Canadian physicians prescribes or hands out some kind of placebo to their often-unknowing patients, a new study suggests.

The seemingly widespread use of sugar pills and other inactive treatments identified by the survey highlights a mounting debate over the issue, with some experts arguing that placebos should be accepted as a legitimate — and side-effect-free — alternative to drugs.

Others say giving patients harmless but chemically inert treatments — especially when disguised as something else — cannot be justified until there is better-quality research proving they actually help.

Many in the profession already seem convinced. Most of the 600 MDs across Canada surveyed by Amir Raz, a McGill University psychiatry professor, and colleagues indicated that they thought placebos do, in fact, have some therapeutic advantage, a paper just published in the Canadian Journal of Psychiatry indicates.