A NEW TRANSDERMAL DELIVERY SYSTEM FOR PILOCARPINE IN GLAUCOMA TREATMENT

We studied the intraocular pressure (IOP)-lowering effect and the side effects of a new transdermal delivery system (TDS) containing pilocar pine. After giving their written informed consent, patients were rando mly assigned to receive a pilocarpine TDS or a placebo TDS. Two patche s, each containing 30 mg of pilocarpine or placebo, were applied to th e supraclavicular skin of 24 patients. The IOP was recorded before and at +12, 16, and 20 h after application. Plasma samples were analyzed for pilocarpine before treatment and 12 and 20 h later via high-perfor mance liquid chromatography. The amount of drug remaining on the derma l patches was analyzed at 20 h. The mean IOP recorded before applicati on was 22.7 +/- 5.8 mmHg. As compared with the placebo TDS, the piloca rpine TDS did not significantly reduce IOP at 12, 16, or 20 h after ap plication (P = 0.42). The mean plasma concentrations were 2.9 ng/ml at 12 h and 1.3 ng/ml at 20 h. The verum TDS showed a residual mean drug concentration of 35.3 mg pilocarpine on the TDS. A substantial amount of pilocarpine was released from the TDS to the dermis, causing detec table plasma levels of pilocarpine at 12 and 20 h after administration . The pilocarpine TDS is a new nonocular pharmaceutical device that sh ould avoid the side effects well known in glaucoma treatment when conv entional eye drops are used.