That and other quality concerns led the US Food and Drug Administration to impose an import alert on its Mohali plant last week, saying the factory, owned by Indias biggest drugmaker by sales, had not ensured manufacturing quality.
Ranbaxy, which gets more than 40% of its sales from the US, did not immediately respond to a request on Wednesday for comment on the USFDA observations. The USFDAs action has dealt another blow to an Indian generic drug industry battered by a rash of American regulatory rebukes.
The import alert issued to Ranbaxy prohibits it from making USFDA-regulated drugs at the Mohali facility and selling them in the US until its methods, facilities and controls are in compliance with good manufacturing standards.
The ban comes just a few months after it pleaded guilty to US felony charges related to drug safety and agreed to $500 million in fines.
During one of the inspections, the USFDA concluded that a black fibre embedded in a tablet was likely either tape remnants on the nozzle head of the machine or a hair from an employees arm that could be exposed on loading the machine, the documents showed.
Ranbaxy said on Tuesday it would review the details of the USFDA import alert and take all necessary steps to resolve the concerns at the earliest.
The USFDA had conducted inspections at Ranbaxys Mohali facility in 2012, resulting in certain observations, Ranbaxy said in the statement. The company believes that it has made further improvements at its Mohali facility... and remains committed to addressing all concerns of the USFDA.
In Ranbaxys case, the USFDA inspections in Mohali also found that a tablet was not within the specified weight limit, the USFDA inspectors wrote.
Other findings by the USFDA included use of dirty glassware, spots and abrasions on the surface of tablets and potential packaging line failure that resulted in unlabeled bottles sent to pharmacies.