Objective: To summarize the pharmaceutics, pharmacokinetics, development, and clinical application of IONSYS, the fentanyl HCl patient-controlled iontophoretic transdermal system for the management of acute postoperative pain.

Data sources: Clinical literature including both primary sources and review articles was accessed through a search of the MEDLINE databases (1980-October 2006). Key search terms included cutaneous analgesia, fentanyl, IONSYS, opioid, postoperative pain, and patient-controlled analgesia (PCA). Additional clinical trial and drug data were supplied by the manufacturer, the ALZA Corporation.

Study selection and data extraction: Review articles, abstracts, and clinical studies related to patient-controlled iontophoretic transdermal fentanyl and postoperative pain management were analyzed. An evaluation of the research exploring IONSYS for the management of acute postoperative pain was conducted. Relevant information was then selected and is provided in this article.

Data synthesis: IONSYS is the first iontophoretic transdermal drug delivery system that utilizes low-level electrical energy to actively transport ionized fentanyl HCl through intact skin. Research has revealed that use of IONSYS for patients with acute postoperative pain is safe, effective, and well tolerated. Phase I-III trials have demonstrated an appropriate dosing range leading to effective analgesia, with minimal adverse effects. The analgesia provided by this system was found to be superior to that of analgesia placebo and equivalent to that of an intravenous morphine PCA.

Conclusions: Data from clinical trials indicated that IONSYS is successful in controlling acute postoperative pain that circumvents the limitations of intravenous patient-controlled analgesia. The use of this system may serve as an alternative modality for the management of acute pain without increasing such adverse effects as bleeding, intravenous catheter infiltration, or manual pump malfunction.