Forensic Determination of Sildenafil and Vardenafil in Seized Evidence

A plastic-wrapped bundle of herbs packaged and sent halfway around the world. A cardboard box filled with blister-packaged counterfeit tablets. A bag of coffee. One-half tablet, either cut or bitten. A single open capsule with only a residue of powder remaining. These are just a few of the samples that have been seized by law enforcement agencies, analyzed by forensic chemists and identified as containing illegally-distributed sildenafil, the active ingredient in Viagra.