Iontophoresis-Based Transdermal Delivery Systems

Abstract

Transdermal iontophoresis is the administration of ionic therapeutic agents through the skin by the application of a low-level electric current. This article presents an overview of transdermal iontophoretic delivery of drugs, including peptides and oligonucleotides. Recent advances in the area of iontophoretic delivery, including devices, hydrogel formulations, safety, clinical relevance and future prospects, are discussed. Electroporation, another method of electrically assisted drug delivery, is also briefly reviewed. Transdermal iontophoresis appears to be a promising technique for the delivery of a variety of compounds in a controlled and preprogrammed manner. Transdermal iontophoresis would be particularly useful in the delivery of hydrophilic drugs produced by biotechnology (peptides and oligonucleotides). However, because of the complex physicochemical properties of peptides, many factors must be carefully considered for the proper design of an iontophoretic drug delivery system for peptides. Iontophoresis has been successfully used in the delivery of small peptides, such as leuprolide and calcitonin analogues, in humans. However, it appears that transdermal iontophoresis may not be a suitable method for the systemic delivery of larger peptides (>7,000D). The combined use of iontophoresis and electroporation may be more effective in the delivery of peptides, proteins, genes and oligonucleotides. The long-term safety of iontophoresis, patient compliance with the technique and the commercial success of this technology are yet to be demonstrated. Iontophoretic delivery of drugs would be beneficial in the treatment of certain skin disorders such as skin cancer, psoriasis, dermatitis, venous ulcers, keloid and hypertrophic scars. Investigations on reverse iontophoresis may yield interesting results that would be useful in the noninvasive measurement of clinically important molecules in the body.

Dermal and Transdermal Drug Delivery Systems: Current and Future Prospects

“…In addition, iontophoresis has failed to significantly improve the transdermal delivery of macromolecules of >7000 Da (Kanikkannan 2002).…”

Transdermal iontophoresis as an in-vivo technique for studying microvascular physiology

“…A number of excellent reviews on iontophoresis as a method for enhanced transdermal drug delivery have been published earlier (Curdy et al, 2001;Dixit et al, 2007;Guy et al, 2000;Kanikkannan, 2002). Here, we will focus on the mechanisms and methodological issues relevant to the use of the iontophoresis in microvascular research.…”

Transdermal Drug Delivery Systems: Skin Perturbation Devices

“…In addition, iontophoresis has failed to significantly improve the transdermal delivery of macromolecules of >7000 Da (32).…”