People who use over-the-counter acne medications are at risk in some instances for severe allergic reactions, including ones that are potentially life threatening.

Health Canada has issued a warning that states topical acne preparations whose active ingredients are benzoyl peroxide or salicylic acid pose a risk for serious allergic reactions. There are currently more than 400 products in Canada with these ingredients.

These reactions range from application-site irritations such as dryness, burning, itching, peeling, redness, and swelling to extreme reactions such as anaphylaxis.

Anaphylaxis is a serious, life-threatening allergic reaction that is most commonly found in relation to foods, insect stings, medications, and latex. The condition, if not immediately treated, can be fatal.

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The Reason for the Alerts

Severe allergy reactions and hospitalizations to acne medication are rare.

Nonetheless, Health Canada issued the alert — called an Information Update and Summary Safety Review — in December, following an assessment that was part of its routine health-product monitoring.

The review was launched after the U.S. Food and Drug Administration (FDA) warned in June 2014 about the risks of reactions to the same ingredients.

In its 2014 alert, the FDA cited statistics from 1969 through 2013. During that time, consumers and manufacturers reported 131 cases of allergic and hypersensitivity reactions associated with acne medications to the FDA, the agency said in the announcement.

Those affected were 86 percent female and ranged in age from 11 to 78. Slightly more than 40 percent of them said their reactions occurred within minutes to 24 hours of use.

Another 40 percent described severe symptoms, including throat tightness, shortness of breath, wheezing, low blood pressure, fainting or collapse. While no deaths were reported in that time period, 44 percent of the patients were hospitalized.

Eric Morrissette, chief of media relations for Health Canada, said his agency will now update the directions of use and warnings sections of its Acne Therapy Monograph for over-the-counter (OTC) topical acne products containing benzoyl peroxide or salicylic acid.

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Causes of Reactions Are Unclear

Who experiences allergic reactions to these medicines?

“An individual’s risk of having an allergic reaction will depend on a number of factors,” Morrissette told Healthline. “Why benzoyl peroxide or salicylic acid causes allergic reactions has not yet been determined. Both products can cause skin irritations, which have been known to lead to allergic reactions.”

He added individuals with a history of allergies, eczema, hay fever, or asthma may also be more at risk of developing allergic reactions to these medications. Over-the-counter acne products may also contain non-medicinal ingredients that may trigger allergic reactions.

Drug allergies are the result of a number of factors and are often unpredictable, he said.

“Allergies to topical benzoyl peroxide and salicylic acid are rare,” he said. “An allergic or hypersensitivity reaction is more likely to occur if inflammation of the skin exists or if the individual using the product is susceptible to the allergen, which elicits an immune response.”

Morrissette said the analysis that contributed to the safety review and the risk warning included scientific and medical literature, Canadian and international adverse-reaction reports, and what is known about the use of these health products both in Canada and internationally.

The updated Health Canada Acne Therapy Monograph will be posted on Health Canada’s website early this year and will be open for public comments, which can include observations from manufacturers of acne products, he said.

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Products in the U.S.

When the U.S. warning, called a Drug Safety Communication (DSC), was announced in 2014, Dr. Mona Khurana, an FDA medical officer welcomed the change.

“There is currently no mention of the possibility of these very severe allergic reactions on the product labels,” she said at the time. “It’s important that consumers know about them and that they know what to do if they occur.”

FDA spokesperson Stephen King told Healthline that “products of concern” are marketed under different brand names such as Proactiv, Neutrogena, MaxClarity, Oxy, Ambi, Aveeno, and Clean & Clear.

“They’re available as gels, lotions, face washes, solutions, cleansing pads, toners and face scrubs,” he said.

King said consumers can find out if an OTC topical acne product contains benzoyl peroxide or salicylic acid by looking at the active ingredients section of the drug facts label on the product package.

Morrissette said Health Canada will request that manufacturers revise the labels on their acne products to the allergy risks outlined in its Summary Safety Review. The FDA will encourage manufacturers to use the drug label to advise consumers how to test the product’s safety before using it for the first time.

Following the national alerts, acne-medication makers have been silent on the topic.

Health Canada has not received any reaction from manufacturers in that country following the publication of the Safety Summary Review and Information Update, Morrissette said. In addition, manufacturers of two popular products did not respond to inquiries from Healthline.

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Reviews and Recommendations

Health Canada and the FDA have similar procedures for reviewing and approving new drugs. Manufacturers conduct clinical trials on new medicines and present them for review. The health agencies then examine clinical-trial results to determine whether a product can be used safely and effectively by consumers.

The FDA identifies hypersensitivity reactions based on voluntary reporting to its Adverse Event Reporting System (FAERS).

“Reporting comes from a variety of sources, including consumers,” King said. “Based on the information reported to the FDA, we cannot determine if the serious hypersensitivity reactions were triggered by the acne product’s active ingredients, benzoyl peroxide or salicylic acid, by the inactive ingredients, or by a combination of both.”

The FDA continues to monitor this product-safety issue, King said. For drugs marketed under the FDA’s regulations for OTC medicine, “labeling changes require a lengthy notice and comment rule-making process,” he said. “At this time, the FDA has not proposed specific required labeling changes related to hypersensitivity for OTC acne products.”

The agency, however, suggests that new users of acne products apply a small amount of the preparation to a small affected area for three days. If no discomfort occurs, they can follow the labeled directions for normal use.