Ranbaxy Laboratories, India's top drugmaker by sales, said it has recalled its cholesterol-lowering drug atorvastatin in the United States, a generic version of Lipitor that largely drove the company's sales in the first of half the year.

The recall will temporarily disrupt supplies of atorvastatin in the U.S. market while it conducts an investigation, Ranbaxy, controlled by Japan's Daiichi Sankyo, said in a statement.

Shares of the company fell more than 2% following the announcement.

"The development will impact the company's credibility to an extent," said Bhagwan Singh Chaudhary, a research associate at the brokerage IndiaNivesh.

"There have been issues in the past (about compliance) and a recall suggests, corrective measures suggested by the U.S. FDA are not being implemented."

The U.S. Food and Drug Administration had banned shipments from some of Ranbaxy's manufacturing plants over compliance issues in 2009. Early this year, Ranbaxy agreed to make broader changes at it plants and agreed to appoint an external auditor to resolve the matter.

Ranbaxy was the first company to launch generic Lipitor in the United States after Pfizer's patent expired on Nov. 30 last year.

The Indian company enjoyed marketing exclusivity for the first six months to May 2012 along with U.S.-based Watson Pharmaceuticals.

Generic Lipitor generated nearly $600 million in sales for Ranbaxy for the first six months, when it had exclusive marketing rights, IndiaNivesh's Chaudhary said.

Ranbaxy has initiated an investigation about the recall and expects to complete it within two weeks, after which the company plans to resume supplies, the company said.