You’ve got to hand it to the folks at Matrixx Initiatives. They managed to convince millions of Americans to paint the inside of their noses and throats with a toxic heavy metal that is ineffective in its stated benefit and destroys the nerves responsible for the sense of smell.
Matrixx marketed Zicam as a cold remedy. There is no evidence that Zicam has any effect on colds, but there is decades of data showing that zinc, the purported active ingredient, can damage the sense of smell. Indeed, since 2006, Matrixx Initiatives has been forced to pay $12 million dollars to 340 people who claimed that Zicam destroyed their sense of smell. Hundreds more lawsuits are still pending.
So how did Matrixx manage to convince Americans to apply a toxic heavy metal to sensitive internal tissues? They called it a homeopathic remedy and that allowed them to avoid having to prove that Zicam was effective or even safe. And, they relied on the gullibility of the American public and its current love affair with all things “natural.”
The Obama Administration is working to close the legal loophole that allows companies to market “natural” remedies without proving that they are effective or even safe. In the meantime consumers can become less gullible. The first step is to understand how we know whether a substance works. Answering the question goes far beyond giving the substance to individuals and asking them about their perceptions.
The study of drug efficacy and safety is pharmacology. Pharmacology can be roughly divided into two areas: pharmacodynamics, how the substance acts on the body and pharmacokinetics, how the body acts on the substance.
Here are some basic questions that must be answered to find out how the drug works on the body:
How does the drug work? What is the active ingredient? What effect does the active ingredient have on the body?
What is the dose-response? In other words, as the dose of drug increases, does the response increase?
What is the ED50, the dose that produces a response in 50% of subjects, also known as the median effective dose?
What is the maximum effect that can be produced by the drug, also known as efficacy?
What is the therapeutic window? For every drug, there exists some concentration which is just barely effective and some dose which is just barely toxic. Between them is the therapeutic window where safe and effective treatment will occur.
In addition, we need to know how the body interacts with the substance.
How does it enter the body?
How is it removed from the body?
Does it have effects on other parts of the body besides its stated therapeutic effect?
What did the makers of Zicam know about their product before they put it on the market? The only thing that they knew is that the active ingredient is zinc. They did no testing that would tell them the mechanism of action, the dose response or even the effect of the zinc on other tissues of the body. Therefore, at no time did they have evidence that the drug was either safe or effective, yet they sold it anyway.
Determining drug efficacy and safety is complex. It is absolutely imperative to study the pharmacodynamics and pharmacokinetics of a substance before anyone can claim that it is effective or safe. As the case of Zicam illustrates, when it comes to “natural” remedies, these questions have not even been asked, let alone answered.
