Unauthorized skin lightening and skin treatment products may pose serious health risks

Hydroquinone is a prescription drug when it is greater than a 2% concentration and a natural health product at a concentration of 2% and under. It is used topically (applied to the skin) to lighten areas of darkened skin caused by different conditions (e.g., sun exposure, skin damage, pregnancy, medications or age). It should not be used by people who are allergic to hydroquinone or who are taking medicines that make their skin more sensitive to light. Hydroquinone is not recommended for pregnant or breastfeeding people, or for children. It should be used with caution in those who have previously had cancer. Side effects include skin reactions such as redness, dryness, cracked skin, burning, stinging, peeling, itching, increased sensitivity to sunlight, sunburn, blisters and scarring. It may cause skin discolouration (i.e., blue or black discolouration or white patches or spots) that, in some cases, can be disfiguring. In laboratory animals, it has been associated with cancer after long-term exposure.

Tretinoin in topical format (applied to the skin) is a prescription drug used to treat acne. Topical tretinoin should not be used during pregnancy as it has been associated with birth defects. It should also not be used by those who are breastfeeding or by children under 12 years old, or by individuals who have inflamed or irritated skin, have a previous skin cancer or undiagnosed skin lesions, who are taking medicines that make their skin more sensitive to light, or who have an allergy to tretinoin. Tretinoin may cause pain, irritation, itchiness, redness, or swelling at the site of application. It may damage skin, change skin colour, and increase sensitivity to sunlight or tanning beds, causing sunburns. Using tretinoin in combination with hydroquinone may increase some of the side effects of tretinoin.

Betamethasone dipropionate, betamethasone valerate and clobetasol propionate are highly potent corticosteroid prescription drugs that are applied to the skin to treat inflammatory skin conditions. Side effects include skin irritation and, with prolonged use, skin weakening or deterioration. Adverse effects from using too much include decreased ability to fight infection, symptoms of adrenal gland suppression (i.e., low blood pressure, low blood sugar, weight loss, muscle pain, gastrointestinal problems and severe fatigue) or Cushing's syndrome (i.e., high blood pressure, high blood sugar, weight gain, muscle weakness, bone loss and severe fatigue), depending on how much has been absorbed. These drugs should not be used by pregnant or nursing people.

Ketoconazole is a prescription antifungal drug typically used to treat skin and scalp infections. It should be used only under the supervision of a health care professional. When applied to skin, common side effects include severe irritation, itchiness and stinging. Contact dermatitis (an itchy or painful rash) and painful allergic reactions have been reported more rarely. Ketoconazole should not be used by pregnant or breastfeeding people unless directed by a health care professional.

Neomycin sulfate is an antibiotic prescription drug and should be used only under the supervision of a health care professional. Side effects include allergic reactions that range from mild skin reactions (itching, rash and hives) to severe, life-threatening allergic reactions (anaphylaxis). Side effects such as damage to nerve tissue or the central nervous system, inner ear, and organs responsible for hearing and balance, and reduced kidney function have occurred in patients taking neomycin orally (by mouth) or when applied on the skin to open wounds or damaged skin. As well, when not used as directed, neomycin sulphate could increase the risk of infections resistant to neomycin or other antibiotics. Neomycin sulphate should not be used by pregnant or breastfeeding people unless directed by a health care professional.