title: Patient-controlled analgesia: therapeutic interventions using transdermal electro-activated and electro-modulated drug delivery.
abstract: Chronic pain poses a major concern to modern medicine and is frequently undertreated, causing suffering and disability. Patient-controlled analgesia, although successful, does have limitations. Transdermal delivery is the pivot to which analgesic research in drug delivery has centralized, especially with the confines of needle phobias and associated pain related to traditional injections, and the existing limitations associated with oral drug delivery. Highlighted within is the possibility of further developing transdermal drug delivery for chronic pain treatment using iontophoresis-based microneedle array patches. A concerted effort was made to review critically all available therapies designed for the treatment of chronic pain. The drug delivery systems developed for this purpose and nondrug routes are elaborated on, in a systematic manner. Recent developments and future goals in transdermal delivery as a means to overcome the individual limitations of the aforementioned delivery routes are represented as well. The approval of patch-like devices that contain both the microelectronic-processing mechanism and the active medicament in a small portable device is still awaited by the pharmaceutical industry. This anticipated platform may provide transdermal electro-activated and electro-modulated drug delivery systems a feasible attempt in chronic pain treatment. Iontophoresis has been proven an effective mode used to administer ionized drugs in physiotherapeutic, diagnostic, and dermatological applications and may be an encouraging probability for the development of devices and aids in the treatment of chronic pain.
authors.affiliation: Department of Pharmacy and Pharmacology, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Johannesburg, 2193, South Africa.
authors.forename: Sunaina
authors.initials: S
authors.lastname: Indermun
authors.forename: Yahya E
authors.initials: YE
authors.lastname: Choonara
authors.forename: Pradeep
authors.initials: P
authors.lastname: Kumar
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Du Toit
authors.forename: Girish
authors.initials: G
authors.lastname: Modi
authors.forename: Regina
authors.initials: R
authors.lastname: Luttge
authors.forename: Viness
authors.initials: V
authors.lastname: Pillay
mesh_terms: D000279:Administration, Cutaneous; D016058:Analgesia, Patient-Controlled / Q000191:economics / Q000379:methods*; D000700:Analgesics / Q000008:administration & dosage* / Q000627:therapeutic use*; D002626:Chemistry, Pharmaceutical; D016503:Drug Delivery Systems; D004558:Electric Stimulation; D006801:Humans; D007260:Infusion Pumps; D007478:Iontophoresis; D009339:Needles; D059408:Pain Management / Q000379:methods*
chemical_list: D000700:Analgesics
keywords: chronic pain; drug transport; electro-conductive hydrogel; iontophoresis; microneedle arrays; patient-controlled analgesia; permeation enhancers; polymeric drug delivery systems; transdermal drug delivery