Transfer of topically applied tetracycline in various vehicles

Abstract

Fifty hospitalized dermatology patients participated in a study to evaluate the transfer of topically applied tetracycline hydrochloride-containing fluorescent ointments, creams, lotions, and tinctures from various sites of application. Patients were examined with a Wood's lamp 24 hours after application to determine the sites and areas of transfer. The topically applied medications did not remain confined to sites of initial application. The anatomic sites of initial application determined the pattern of transfer. Certain patterns of transfer were characteristic among groups of patients and for specific patients. The vehicle of the topical preparation greatly influenced the extent and sites of transfer.

The clinical benefit of moisturizers

“…Only 50% of applied creams were found to remain on the surface after 8 h 171 . Transfer of the actives to surrounding surfaces appears to be easier from creams and ointments than from lotions and tinctures 172 …”

Wood’s light in dermatology

“…This knowledge has proved useful for studying the transfer of topically applied medications to other body sites. 33 The yellow fluorescence of the lunulae 34 and the nails 35 has also been observed in patients taking oral tetracycline. This fact can be helpful in distinguishing tetracycline-induced nail pigmentation from other causes of yellow nails.…”

Moisturizers: The slippery road

“…Only 50% of applied creams were found to remain on the surface after 8 h.[ 53 ] Transfer of the actives to the surrounding surfaces is easier for creams and ointments than lotions and tinctures. [ 54 ] Depending on the severity of xerosis, the frequency of application can vary between 1 and 3 times daily, especially after bath.…”