A maker of more than half a million recalled contact lenses blamed for reports of corneal tears and other injuries acknowledged Wednesday that some of its users may have experienced “severe eye pain.”

Officials with CooperVision Inc. of Fairport, N.Y., urged wearers of Avaira Toric contact lenses who believe they’ve suffered harm to stop the using the products, which were first voluntarily recalled on Aug. 19 because of problems with residue left behind during manufacturing.

“Not everyone experiences the same symptoms,” company officials said in a statement, which recommended that affected users seek medical care.

The advice came in a press release issued after federal health officials pressured CooperVision to more broadly publicize its recall of an estimated 600,000 contact lenses. On Wednesday, a spokeswoman for the federal Food and Drug Administration said the agency was continuing to review CooperVision’s response.

“The FDA is evaluating the notification that CooperVision issued today and will advise CooperVision of any concerns that it raises. Failing resolution of those concerns, the FDA may issue separate public communication,” spokeswoman Morgan Liscinsky said in a statement.

CooperVision originally said they’d received only limited reports of problems including hazy vision and discomfort. But more than a dozen people contacted by msnbc.com reported more serious problems, including corneal abrasions and corneal tears that required emergency care.

The FDA has received about 15 complaints through its adverse event reporting system about the Avaira Toric lenses, which were introduced in April and recalled in August, Liscinsky said. Those reports included complaints of corneal tears, she added. Recalls are voluntary, with the FDA advising companies about appropriate levels of public notification and other action.

Some users have indicated that other brands of CooperVision contact lenses have caused problems as well, but Liscinsky said she couldn’t speculate about other brands being implicated in a recall.

CooperVision officials said they’ve sent worldwide notifications to more than 9,000 Avaira Toric customers and contacted more than 7,000 U.S. eye care practitioners who have received or sampled the lenses.

Customers can check to see if their lots are affected on the company’s website, www.coopervision.com/recall, or call a toll-free consumer hotline at 1-855-526-6737.

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