Users of the nasal spray Zicam Cold Remedy have filed a proposed class action lawsuit, claiming the popular over-the-counter product robbed them of their sense of smell.

A spokesman for Phoenix-based Matrixx Initiatives Inc., which distributes Zicam, on Monday said the lawsuit had been prompted by media reports on a flawed medical study and was without merit.

The lawsuit also seeks unspecified damages from retailers such as Walgreen Co., Wal-Mart Stores Inc., Costco Wholesale Corp., Kroger Co., Rite Aid Corp., Safeway Inc.

Officials at Walgreen, Kroger and Rite Aid had no immediate comment on the lawsuit. Officials at Wal-Mart, Costco and Safeway could not be reached for comment.

The lawsuit, filed in Arizona Superior Court last month and made public on Monday, claims Matrixx and Botanical Laboratories Inc. sold the homeopathic spray and gel without proper testing.

Zinc nasal sprays have been touted by doctors and some researchers as a way to cut the length and severity of colds. But a University of Colorado study, presented in the American Journal of Rhinology’s May-June issue, linked zinc sprays to loss of the sense of smell, or anosmia.

The company has strongly defended Zicam as safe, and contends the University of Colorado research relied on a “very, very weak anecdotal report about one man in his 50s who had a lot of risk factors for loss of smell.”

“The product was marketed since 1999 and this was not an issue until this (study) got into the media,” said Robert Murphy, a spokesman for Matrixx.

Since the start of the year, shares of Matrixx have lost about 27 percent. The stock has rebounded from a low of $7.26 in mid-July and closed on Monday at $13.01 on Nasdaq, down 1.4 percent on the day.