NEW YORK (NEWSnet/AP) — Federal regulators are warning consumers that now-recalled lots of the Tydemy birth control pill “may have reduced effectiveness” due to decreased levels of a key ingredient of the product.

Lupin Pharmaceuticals, which manufactures Tydemy, notified customers on Saturday that it was voluntarily recalling two batches of the oral contraceptive — after one lot tested low for ascorbic acid and high “for a known impurity.”

Inadequate ascorbic acid “could potentially impact the effectiveness” of the birth control, Lupin said in a company announcement published by the Food and Drug Administration, and that could result in unexpected pregnancy.

The Tydemy lots under recall were distributed across the U.S. from June 2022 through May 2023. The products can be identified by their lot codes — L200183 and L201560 — and expiration dates of January 2024 and September 2024, respectfully.

Lupin is instructing Tydemy patients to continue taking their medication — but immediately contact a health care provider “for advice regarding an alternative contraceptive method,” the FDA said, if their medication was impacted by the recall.

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