Health Canada is warning Canadians that a product used to help people sleep could be habit forming when used over a period of months.

Eden Herbal Formulations Sleep-Ease Dietary Supplement has an undeclared drug called estazolam, the agency said on Wednesday.

The supplement is not authorized for sale in Canada, but was distributed at the Evergreen Acupuncture Clinic in Calgary.

Side-effects associated with the drug estazolam can include dizziness, drowsiness, confusion, depression, loss of memory and hallucinations.

Health Canada says consumers should not take the supplement and if they find it for sale anywhere in the country, they should call the Health Products and Food Branch Inspectorate at 1-800-267-9675.