The benefits of Diane-35, an acne drug that is prescribed as birth control, outweigh its risks, Health Canada says.

In Canada, Diane-35 is approved for temporary treatment of severe acne — with associated symptoms of high levels of male hormone, including seborrhea (oily skin) and mild hirsutism (excessive body hair) — in women who are unresponsive to other available treatments.

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Health Canada says its safety review of Diane-35 supports current labelling and use. (Regis Duvignau/Reuters)

The drug is often prescribed "off-label" as a contraceptive.

The regulator said Friday that its review of the safety of Diane-35 concluded its benefits continue to outweigh the risks, when used as authorized.

Health Canada announced the review in January, following France's decision to withdraw sales of the medication in response to the deaths of four women over the last 25 years.

Blood clots are a rare but well-known side-effect of oral birth control pills and other hormonal products such as Diane-35, said the federal department said at the time, noting that the product monograph for the drug contains clear warnings about this potential adverse effect.

Blood clot risks

Also on Friday, a committee at the European Medicines Agency concluded that the benefits of Diane-35 and its generics outweigh the risks when measures are taken to minimize the risk of thromboembolism — formation of blood clots in the veins and arteries.

In February, the Society of Obstetricians and Gynecologists of Canada concluded that the risk of venous thromboembolism in Diane-35 users is very low and comparable to that other combined hormonal contraceptives.

Health Canada has said Diane-35 should not be used in patients with a medical history that puts them at risk for blood clots, including smoking, being overweight or a family history of the condition.

The department has previously warned about the increased risk of blood clots associated with Diane-35 compared with estrogen/progestogen contraceptives, and has cautioned against using the acne drug for birth control.

Doctors should be told about any medications being taken, including Diane-35, Health Canada said.

In 2003, a CBC News investigation revealed that thousands of Canadian women were taking the drug solely for birth control, unaware of the potential risks.