In June of 2009, the Food and Drug Administration (FDA) submitted a news release advising consumers that the use of certain Zicam products may result in the loss of smell (ansomnia). According to the frequently asked questions section at the Zicam homepage, Zicam is available in a number of different preparations and is advertised as being an over-the-counter (OTC) medicine that shortens the duration and severity of the common cold when it is taken at the first sign of a cold. Because Zicam is considered to be a “homeopathic” remedy, it is not required to undergo the stringent safety evaluations or testing that other more conventional drugs undergo before approval.
Recently, scientists at the University of Washington published an article in the online journal, PLos ONE, confirming this news release from the FDA. These scientists presented data stating that the homeopathic cold remedy Zicam can irreversibly damage nasal tissue in mouse models, and in humans. The purpose of the present study was to test Zicam and several other commonly used drugs that with intranasal routes of administration, such as Afrin, Nasacort, lidocaine, epinephrine, and saline. The data from those studies on a mouse demonstrated that Zicam administration resulted in the death of olfactory cells in the neuroepithelium. The death of these particular cells is thought to be responsible for the newfound unresponsiveness of these mice when presented with new or novel scents.
Using nasal tissues donated by human subjects, Zicam application, but not the other drugs, also demonstrated an increase in cellular damage. Histological studies on the human tissue confirmed that every human tissue sample examined demonstrated severe tissue damage and necrosis (cell death). Interestingly, two articles available on the Zicam homepage confirm the ability of Zicam to shorten the duration of colds, although, both studies report that the adverse effect of Zicam administration was “nasal stinging.”
Tags: Zicam