1. Why did the FDA issue a statement about Zicam? There were some 130 reports from consumers that might have contracted anosmia (lack of smell) after using Zicam. In addition, the FDA uncovered another 800 complaints that were reported to the manufacturer (Matrixx Initiatives, Inc.). This is a relatively large number of adverse events that need to be investigated. The company’s statement says that the FDA action is “unwarranted”, but does not provide scientific evidence to support that statement.
2. Anosmia doesn’t sound that bad. A temporary or permanent loss of smell is more serious than simply not being able to smell. If you contracted anosmia, you couldn’t tell if your food was spoiled, if your house was on fire, or enjoy the food you eat. In other words, the loss of your sense of smell can put you in danger.
3. The company claims that common viruses cause anosmia. The active ingredient in Zicam is zinc gluconate. It has already been reported in respected journals that intranasal zinc (at the concentrations found in Zicam) does cause anosmia. Yes some viral infections cause anosmia, but the effect is not immediate, and the two reports eliminated viral infections as a possible cause.
4. But Zicam works! As I discussed yesterday, most of the research indicates that zinc gluconate has no or minimal effect on the duration or course of the disease. At best, Zicam may reduce the length of the disease, but a common cold last 6-10 days on average. By random chance, the patient may have an infection that spontaneously resolves itself on the lower end of the scale.
5. So Zicam may or may not reduce the length of my cold, yet it has a small, but significant possibility that I might lose my sense of smell? Yes, the risk/benefit ratio is a bit troubling. There have been about 1,000 reports of anosmia, while the company claims that over 1 billion doses have been sold. Even though it’s probable that many cases of anosmia have not been reported, and certainly not all 1 billion doses sold were used, using these extreme numbers, we get about a .0001% risk of anosmia. We do things in life that have a much higher risk of an adverse event. However, we manage risk by accepting a certain level weighed against a benefit. All drugs sold have a risk, some significant. But in accepting that risk, physicians and patients are convinced of a benefit. If the benefit is small, nonexistent, or worthless (reducing the course of a common cold from 7 to 6 days would be essentially worthless), and risk is serious, though rare, I would conclude that the risk isn’t worth the benefit. At a minimum, I should know this information upfront so that I can make an informed decision.
6. So why aren’t these products regulated by the FDA more closely. (Comments revised on 06/18/09) Zicam specifically wasn’t regulated closely, because it was considered a homeopathic potion, and as such was exempt from FDA regulation by the Dietary Supplement Health and Education Act of 1994 (DSHEA). However, Zicam isn’t really a homeopathic solution (which are diluted so much that there are zero molecules of the active compound in solution), since the concentration of zinc gluconate exceeds 2 parts per 100 which means there are billions and billions and billions of molecules in a one spray of your nose. The FDA has a high burden of proof to regulate products that are covered by the DSHEA, but Zicam has met that proof. Zicam should scientifically prove its safety and efficacy claims in a drug application to the FDA. I am no defender of homeopathy (there is no way that 0 molecules of any substance in water will have any effect except taking money from your wallet), but it’s ironic that Zicam, which is not a homeopathic product, is being criticized by “real” homeopaths for not being a real homeopathic potion. Of course, that’s not the point, it’s that Matrixx characterized its product as homeopathic so that it would not be regulated closely. Well, it’s receiving it’s comeuppance from the FDA and the stock market (Matrixx shares have dropped from around $20 to $6 per share in one day).

Tags: Quackery, Homeopathy, Zicam, Pseudoscience, FDA, Alternative medicine, Anosmia