The feds slapped Dollar Tree with a warning this month over the company’s imports of potentially dangerous over-the-counter drugs.

The discount retailer has received acne treatment pads and other products from foreign manufacturers that have committed “serious” violations of federal standards, the US Food and Drug Administration said in a Nov. 6 warning letter to the company.

The letter, released Thursday, demands the Virginia-based company put together a plan to make sure it does not import or deliver any more “adulterated” drugs.

“The importation and distribution of drugs and other products from manufacturers that violate federal law is unacceptable,” Donald D. Ashley, the director of the Office of Compliance in the FDA’s Center for Drug Evaluation and Research, said in a statement. “In this case, Dollar Tree has the ultimate responsibility to ensure that it does not sell potentially unsafe drugs and other FDA-regulated products to Americans.”

Regulators’ concerns revolve around manufacturers Dollar Tree used to produce its “Assured Brand” drugs and other products sold at its stores. The FDA says Dollar Tree’s contractors showed a pattern of violations, including a failure to test raw materials or finished drugs for quality and pathogens.

The manufacturers had received their own FDA warning letters in recent years and were also placed on import alert, a measure meant to stop the flow of sketchy products into the US, federal officials say. Dollar Tree claimed it stops importing from companies when their drugs are put on import alert, but the FDA found that was not always true, according to the letter.

Dollar Tree is cooperating with the FDA and expects to meet the agency’s requirements, said Randy Guiler, the company’s vice president of investor relations. He said the products mentioned in the FDA’s report are “topical, and not ingestible.”

“We are committed to our customers’ safety and have very robust and rigorous testing programs in place to ensure our third-party manufacturers’ products are safe,” Guiler said in a statement, adding that Dollar Tree plans to meet with the FDA in the near future.