OTTAWA – Health Canada has completed a safety review of human health products and veterinary drugs containing gentian violet and has found that exposure to these products may increase the risk of cancer. Given the seriousness of this risk, Health Canada is advising Canadians to stop using all human and veterinary drug products containing gentian violet.
Gentian violet is an antiseptic dye used to treat fungal infections. Products containing gentian violet have been used on the skin, on mucous membranes (inside the nose, mouth or vagina), on open wounds, or on the nipple of a nursing mother to treat oral thrush in infants.
Health Canada’s review was triggered by the World Health Organization’s Codex Alimentarius Commission’s recommendation on the potential risk of cancer associated with veterinary drug residues in foods, including gentian violet. Although the Commission’s recommendations were specific to food residues, Health Canada reviewed the safety of human non-prescription drugs, veterinary drugs and medical devices containing gentian violet.
After completing two safety assessments, the Department concluded that, as with other known cancer causing substances, there is no safe level of these products, and therefore any exposure to these products is a potential cause for concern.
What you should do
- Stop using all drug products that contain gentian violet, including on animals. Products for humans should be returned to a pharmacy for proper disposal. Animal owners can discuss options for the safe disposal of their products with their veterinarians or local pharmacies.
- Do not use dressings containing gentian violet for longer than six months or if you are pregnant or nursing.
- Consult your health care professional if you have used any health products containing gentian violet and have health concerns.
- Read product labels to verify that health products have been authorized for sale by Health Canada. Authorized health products have an eight-digit Drug Identification Number (DIN), Natural Product Number (NPN) or Homeopathic Drug Number (DIN-HM). You can also check whether products have been authorized for sale by searching the Drug Product Database, Medical Devices Active Licence Listing (MDALL) and Licensed Natural Health Product Database.
- Report any health product-related adverse reactions or complaints to Health Canada.
- Contact Health Canada at 1-800-267-9675 or by completing an online complaint form if you find a drug product that contains gentian violet in the Canadian marketplace.
What Health Canada is doing
Health Canada worked with all manufacturers with licensed drug products containing gentian violet to remove them from the market.
Human Non-prescription Drugs:
There was only one non-prescription drug product containing gentian violet marketed in Canada. Gentiane Violet Liquid Topical is an antiseptic used to treat infections of the skin and mucous membranes. This product is also known to be used by some nursing mothers to treat oral thrush in infants. The manufacturer has voluntarily stopped marketing this product in Canada and its product licence has been cancelled. The manufacturer indicated that the product was no longer available on the market, so no recall was required.
In Canada, there were nine registered veterinary drug products containing gentian violet, four of which were available as of April 2019: Blu Kote Dr Naylors, Cristisol, Guard and Wound Spray, and Wound Clear Spray. These products were used to treat surface wounds and eye infections in food-producing and companion animals (e.g., cattle, poultry, horses, dogs, cats). All manufacturers have voluntarily stopped marketing these products, their product licences have been cancelled, and any products that were on the Canadian market have been recalled.
There are currently three licensed medical devices on the market that contain gentian violet. They are all sterile dressings made of polyurethane foam, and are used for wounds such as sores, skin graft sites, abrasions and cuts. They are all made by one manufacturer (Hydrofera). The risk assessment for these devices found that the gentian violet is unlikely to come into direct contact with the skin, therefore these products do not posean increased risk of cancer when used for a short time and in most people. The Department has requested that the manufacturer update the product labels to state that these products should not be used for longer than six months and should not be used by pregnant or nursing women as a precaution because of the lack of information available to support these uses.
Should the Department identify unauthorized health products containing gentian violet being sold in Canada, it will take appropriate and timely action to protect the health and safety of Canadians.