1. ¹JL Yeager & Associates, Inc., Lake Forest, Illinois, USA
2. ²Scintiprox, Inc., Indianapolis, IN, USA

Correspondence: J Yeager, PhD, JL Yeager & Associates, Inc., Lake Forest, Illinois 60045, USA. E-mail: jlyeager@aol.com

Received 22 March 2004; Revised 4 October 2004; Accepted 4 October 2004; Published online 11 November 2004.

Abstract

Retention and migration of a specially designed alprostadil transdermal cream was assessed after single-dose administration to the glans meatus of the penis. Seven men were enrolled in this two-way crossover study. Three subjects self-administered the radio-labeled alprostadil transdermal cream (100 mg of cream containing 300 g alprostadil) by inserting the tip of the dispenser into the meatus. In three others, the dose was administered by dispensing the cream dropwise into the metal opening without touching the penis (the preferred and directed method). Retention and migration of the cream mass was measured in the penis with a gamma scintillation camera. The alprostadil transdermal cream was retained in the fossa navicularis at or near 99% in five of six subjects regardless of the method of dosing, thus indicating that the cream formulation performed as designed. A mild, transient burning sensation in the penis was the most common adverse event.