The study by Romanowski and associates [1] regarding the efficacy of minocycline in the treatment of nongonococcal urethritis and mucopurulent cervicitis leaves me confused. Their results appear to support the hypothesis that minocycline is as effective as doxycycline, but it seems a bit premature to suggest that their findings "support the administration of minocycline 100 mg as a single nightly dose" over doxycycline [1].

The crux of their recommendation may be based on improved compliance. This factor was not evaluated in their study. Their recommendation may be based on the fewer side effects seen with minocycline. However, side effects were specifically elicited, and, although a grading system was used to measure their severity, this system was not applied when comparing the minocycline and doxycycline groups.

I raise these issues because the cost of minocycline is as much as 10 times greater than that of doxycycline, even for once-daily dosing. This cost represents only the acquisition cost for the pharmacist. Very often, cost is overlooked when considering compliance, especially for the population most at risk for nongonococcal urethritis and mucopurulent cervicitis. It is the age group studied in this article that is most likely to be uninsured and to incur the added cost directly out of pocket [2].