Birth control pills recalled because they may have reduced effectiveness, FDA warns

The pharmaceutical company behind the birth control pill Tydemy is recalling two batches of the drug because they may have reduced effectiveness.

Lupin, the New Jersey-based drugmaker, announced Saturday that it was recalling the batches after tests showed the pills had decreased levels of ascorbic acid, an inactive ingredient, and high levels of a "known impurity."

"This could potentially impact the effectiveness of the product which could potentially result in unexpected pregnancy," the company's announcement said.

The Food and Drug Administration similarly warned consumers on Tuesday that the low levels of ascorbic acid — better known as vitamin C — in the Tydemy pills could reduce their effectiveness in preventing pregnancy.

However, Lupin and the FDA said they have “not received any reports of adverse events” related to use of the pills.

The affected batches were distributed between June 3, 2022 and May 31 of this year and have expiration dates of January or September 2024.

Lupin’s news release advises patients taking Tydemy to continue doing so in the short term and to “immediately contact their pharmacist, physician, or medical provider for advice regarding an alternative treatment.”

The company did not immediately respond to a request for more information about the impurity in the pill and the role ascorbic acid plays in it.

The recalled batches can be identified by the lot numbers listed on the packaging: One of the batches, consisting of a pack of 28 pills, is labeled with lot number L200183, while the other consists of three packs of 28 pills and has the lot number L201560.

Patients who experience complications while taking the pill should contact their health provider and can report their concerns to the FDA's MedWatch Adverse Event Reporting program, according to Lupin's announcement.

The company has also asked pharmacists and retailers to "discontinue distribution of the recalled product lots immediately."

This article was originally published on NBCNews.com