Zinc For Colds Losing Its Luster
Users of some products reporting loss of smell, tasteMar 30, 2004 | Los Angeles Times
The safety of zinc gluconate nasal sprays taken to ease symptoms and shorten the duration of the common cold is under review following reports that people lost their sense of smell after using the products.
The reports involve people who used Zicam Cold Remedy nasal gel or Cold-Eeze Cold Remedy nasal spray, both of which are sold over the counter. At least five lawsuits have been filed across the country, according to court documents, and several physicians said they had examined patients who complained of a severe burning sensation and loss of smell and taste after using one of the products.
The Food and Drug Administration has received reports from patients and is reviewing the information, said Jason Brodsky, an agency spokesman.
Officials from Matrixx Initiatives, which makes Zicam, and Quigley Corp., maker of Cold-Eeze, said they did not believe their products were harming people. Tom Clarot, vice president of research and development at Matrixx in Phoenix, said there were no reports of diminished or lost sense of smell among 400 people who participated in clinical studies of Zicam.
Albert Piechotta, a spokesman for Quigley in Doylestown, Bucks County, said there were no reports of problems among 80 people involved in a study of Cold-Eeze. Both studies were submitted to the FDA before the drugs could be marketed as homeopathic remedies.
Both companies said the occurrence of anosmia (the clinical term for loss of smell) among some users of the zinc sprays might be a coincidence. They said anosmia was most often caused by viruses, which produce the cold symptoms that prompt people to use the sprays.
"The Quigley Corp. can empathize with people who suffer this or any medical condition, but do not believe at this time that there is a greater propensity for this problem when using our nasal spray product," Piechotta said.
It's unclear exactly how many reports have been made about health problems involving Zicam or Cold-Eeze; neither the companies nor the FDA would disclose numbers of complaints. But a handful of doctors who specialize in treating conditions involving taste and smell in California, Colorado, Connecticut and Illinois said they had seen patients who complained of a severe burning sensation followed by inability to smell or taste after spraying their noses with one of the products.
Without any science associating zinc gluconate with a permanent loss of smell, "what really needs to be done is more research," said Dr. Richard L. Doty, director of the Smell and Taste Center at the University of Pennsylvania Medical Center.
More than 10 million people have purchased intranasal Zicam since it hit the market in 1999, according to Matrixx. Cold-Eeze spray reached store shelves about a year ago.
Last September, Dr. Bruce Jafek, an otolaryngologist at the University of Colorado School of Medicine, reported at the American Rhinological Society meeting on 10 cases of anosmia among zinc gluconate users.
In February, Matrixx assembled a panel of scientists who recommended additional studies. One will assess zinc gluconate toxicity in animals. Another will determine which human nasal tissues Zicam spray reaches. A third will review health insurance data and anecdotal reports to determine the incidence of anosmia.
Penny Sugar, 57, of San Diego said she lost her sense of smell after she tried Zicam spray for her cold symptoms. Last week she learned her senses of smell and taste were permanently gone.
Dr. Christian de Virgilio, a 42-year-old general and vascular surgeon at Harbor-UCLA Medical Center in Torrance, took Zicam Sept. 22. "I immediately experienced this horrific, almost unbearable burning," he said. "The next day, I had no taste, no smell, and it didn't come back."
Anosmia has not been associated with zinc nasal swabs or zinc gluconate cold lozenges. Zicam Cold Remedy comes in nasal spray, swabs, oral mist, chewables and tablets. Cold-Eeze makes lozenges, spray, pops and sugar-free tablets.
Some ear, nose and throat specialists suggest the difference is that the sprays have the potential to come into direct contact with the olfactory cleft, a patch of tissue high in the nose containing the olfactory nerve. Although some specialists think the force of the spray may send the product high into the nose, Dr. Terence M. Davidson, director of UC San Diego's Nasal Dysfunction Clinic, said anosmia may result from misusing the product by sniffing deeply while spraying.
The directions on Zicam's package specifically state: "To help avoid irritation, do not sniff up gel." The instructions are slightly different for Cold-Eeze, telling users to "spray once into each nostril and inhale through the nose slowly and deeply."
Dr. Allen M. Seiden, medical director of the University of Cincinnati Taste and Smell Center, suspects anosmia among zinc spray users is underreported but still rare because congestion from colds might "prevent the spray from reaching the olfactory cleft."
Existing studies have convinced some doctors that zinc can be toxic to the nose.
In the 1930s, when Canadian doctors gave intranasal zinc sulfate to thousands of children to stem the spread of polio, some developed anosmia.
For decades, researchers have used zinc compounds to eliminate the sense of smell in laboratory animals. Matrixx and Quigley counter that zinc gluconate is a different product.
In December 1999, Dr. Alan Hirsch, director of the Smell and Taste Treatment and Research Foundation in Chicago, saw a 47-year-old man who had used Zicam to prevent a cold. Hirsch reported at an April 2000 conference that the man immediately experienced severe pain and anosmia. To date, Hirsch has seen about 50 such patients.