Iontophoretic Patch Research Articles

Ambient Moisture-Driven Self-Powered Iontophoresis Patch for Enhanced Transdermal Drug Delivery.

Iontophoretic transdermal drug delivery (TDD) devices are known to enhance the transdermal transport of drugs. However, conventional transdermal iontophoretic devices require external power sources, wired connections, or mechanical parts, which reduce the comfort level for patients during extended use. In this work, a self-powered, wearable transdermal iontophoretic patch (TIP) is proposed by harvesting ambient humidity for energy generation, enabling controlled TDD. This patch primarily uses moist-electric generators (MEGs) as its power source, thus obviating the need for complex power management modules and mechanical components. A single MEG unit can produce an open-circuit voltage of 0.80V and a short-circuit current of 11.65µA under the condition of 80% relative humidity. Amplification of the electrical output is feasible by connecting multiple generator units in series and parallel, facilitating the powering of certain commercial electronic devices. Subsequently, the MEG array is integrated with the TDD circuit to create the wearable TIP. After 20 min of application, the depth of drug penetration through the skin is observed to increase threefold. The effective promotion effect of TIP on the transdermal delivery of ionized drugs is corroborated by simulations and experiments. This wearable TIP offers a simple, noninvasive solution for TDD.

Advancing Transdermal Delivery by Zn/Ag-Electrode-Printed Iontophoretic Patch with Self-Generating Microcurrents

This study aimed to evaluate Zn/Ag-electrode-printed patches for the transdermal delivery of small molecules through iontophoresis. The Zn/Ag-electrode-printed patches interact with biological liquid electrolytes and generate suitable microcurrents for the iontophoretic delivery of small molecules across the skin. In fluorescein permeation studies, Zn/Ag-electrode-printed patches increased the transdermal depth of fluorescein into the dermis, while the permeation of fluorescein was limited when Zn/C-electrode-printed patches were tested. Further permeation experiments were conducted with 3D skin models, which showed a similar trend to the above, indicating that Zn/Ag-electrode-printed patches had a higher penetration rate compared to the blank. Studies using acetyl hexapeptide-8 as a peptide drug model and sodium ascorbyl phosphate (SAP) as a hydrophilic derivative of ascorbic acid showed that the iontophoretic patch with Zn/Ag electrodes promoted more penetration of drugs than unprinted patches. The permeation of SAP exhibited a two-phase profile with a relatively rapid permeation followed by a sustained, slower permeation. The permeation of acetyl hexapeptide-8 was slower due to its higher molecular weight, but the iontophoretic patch increased the permeation up to 1.5 times more than the unprinted patch. The microcurrent generated by the patch drives the transport of small molecule components through the skin, for the controlled and efficient delivery of therapeutic agents. The flexible design, efficient microcurrent generation, and stable electrodes make the Zn/Ag-electrode-printed patch a promising tool for transdermal drug delivery.

Remote-controllable dosage management through a wearable iontophoretic patch utilizing a cell phone.

With regard to medical treatment through operations, remote control is possible, however, the area of remote-controllable drug treatment is yet to be established. In this study, a prototyped remote-controllable dosage management system that allows patients and caregivers to administer therapeutic drugs via an internet line without touching the dosage device or formulation was developed. This system consists of a transmitter (System A) located away from the patient, and a dosage device (System B) equipped with a receiver (B1), dosage management unit (B2), and a drug treatment unit (B3) that can be installed on the patient. Additionally, Bluetooth® is adopted to communicate from System A to System B. In the present study, System A was incorporated into a cell phone, and System B was a constant-current iontophoresis (IP) device, which was applied on excised pig skin. Sodium salt of betamethasone phosphate (BP-Na+) was selected as a model drug, and the in vitro skin permeation of BP- was evaluated. As a result, by transmitting the administration information incorporated in System A through B1 to B2, the optimal current was passed between the IP electrodes in B3, and the skin permeation of BP- was obtained by remote control. That is, the skin permeation of BP- was obtained by the current flowing from the IP device. The permeation amount decreased when the voltage load was stopped. These results suggested that remote control from System A enables dosing management of bioactive substances from dosage devices applied on the skin, intracutaneously, or subcutaneously without being near the patient. Although various trials are still required to complete the remote-controlled system, the patient does not have to go to the hospital except to take injections. Such drug administrations would lead to decreased medical expenses and increased quality of life for patients.

Advances in microneedle-based transdermal delivery for drugs and peptides.

Transdermal drug delivery is a viable and clinically proven route of administration. This route specifically requires overcoming the mechanical barrier provided by the Stratum Corneum of epidermis and vascular and nervous networks within the dermis. First-generation Transdermal patches and second-generation iontophoretic patches have been translated into commercial clinical products successfully. The current review reports different studies that aim to enhance the transdermal delivery of biopharmaceutical using microneedles and their effect on drug delivery. Microneedles (MN) are the micron-scale hybrid between transdermal patches and hypodermic syringes. Microneedles are tested and proven to show better delivery of the drugs, overcoming the drawbacks of hypodermic syringes. Multiple microneedles designs have been fabricated i.e. solid, coated, hollow, and polymer microneedles. Hollow microneedles are shorter in length but similar to hypodermic needles and have pore for infusion of liquid formulation of the drug. Solid microneedles a patch is applied after creating a hole in the skin; Drugs are coated on the surface of Coated microneedles; Polymer microneedles can be of different types like dissolving, non-dissolving or hydrogel-forming made up of polymers. Various advantages and limitations associated with the use of these techniques are discussed. Delivery of peptide and protein molecules with microneedles represents a significant opportunity for a better clinical outcome and hence value creation compared to standard injectable routes of administration. The advancement in various formulation and microfabrication techniques are currently being focused to aid the delivery of protein drugs via microneedles. The most recent advances and limitations in Microneedles -mediated protein and peptide delivery were discussed.

Current profile controlled transdermal delivery of pramipexole from an iontophoretic patch system in vitro and in vivo

The objective was to evaluate the transdermal iontophoretic delivery of pramipexole using constant and complex multi-phasic current profiles from an iontophoretic patch system in vitro and in vivo. Preliminary in vitro experiments were performed to optimize iontophoretic patch design and configuration. “Single” compartment systems containing only pramipexole dihydrochloride, and designed to maximize delivery efficiency, suffered from an insufficiency of chloride ions with anodal electrochemistry passing from an Ag/AgCl couple to an Ag dissolution electrode. Addition of NaCl to provide more chloride ions decreased pramipexole delivery efficiency due to competition between pramipexole and sodium cations. A “two-compartment” iontophoretic patch where the drug reservoir was separated from the anodal compartment, which now included NaCl, was shown to be a good compromise since it ensured Ag/AgCl electrochemistry at the anode and an acceptable delivery efficiency. In vivo studies using this iontophoretic patch demonstrated that the plasma concentration of pramipexole closely followed the variation of the applied continuous and multi-phasic current profiles and underlined the control provided by iontophoresis and its unique ability to rapidly change drug input rates. The applied current density and duration of current application were also shown to modulate pramipexole delivery to the brain and CSF.

Towards the advance of a novel iontophoretic patch for needle-free buccal anesthesia

The aim of this work was to develop a mucoadhesive iontophoretic patch for anesthetic delivery in the buccal epithelium. The patch was comprised of three different layers, namely i) drug release (0.64 cm2); ii) mucoadhesive (1.13 cm2); and iii) backing (1.13 cm2). Prilocaine and lidocaine hydrochlorides were used as model drugs (1:1 ratio, 12.5 mg per unit). An anode electrode (0.5 cm2 spiral silver wire) was placed in between the drug release and mucoadhesive/backing layers to enable iontophoresis. Surface microscopy; mechanical and in vitro mucoadhesive properties; drug release kinetics and mechanism; and drug permeation through the porcine esophageal epithelium were assessed. Topographic analysis evidenced differences in the physical structures for the several layers. All layers presented suitable handling properties i.e., flexibility, elasticity and resistance. Both the release and mucoadhesive layers presented features of a soft and tough material, while the backing layer matched the characteristics of a hard and brittle material. A synergy between the drug release and mucoadhesive layers on the mucoadhesive force and work of adhesion of the tri-layered patch was observed. Passive drug release of both drugs fitted to First-order, Hixson-Crowell and Weibull kinetic models; and the release mechanism was attributed to anomalous transport. Iontophoresis remarkably enhanced the permeation of both drugs, but mainly prilocaine through the mucosa as evidenced by the permeability coefficient parameter (3.0-fold). The amount of these amino amide salts retained in the mucosa were also equally enhanced (4.7-fold), while the application of a tiny constant electric current (1 mA·cm−2·h−1) significantly decreased the lag time for lidocaine permeation by about 45%. In view of possible in vitro / in vivo correlations, the buccal iontophoretic patch displays a promising strategy for needle-free and patient-friendly local anesthesia in dentistry.

Semi-interpenetrating chitosan/ionic liquid polymer networks as electro-responsive biomaterials for potential wound dressings and iontophoretic applications

In this work, electro-responsive chitosan/ionic liquid-based hydrogels were synthetized for the first time, envisaging the development of iontophoretic biomaterials for the controlled release/permeation of charged biomolecules. The main goal was to enhance and tune the physicochemical, mechanical, electro-responsive, and haemostatic properties of chitosan-based biomaterials to obtain multi-stimuli responsive (responsive to electrical current, ionic strength, and pH) and mechanically stable hydrogels. To accomplish this objective, polycationic semi-interpenetrating copolymer networks (semi-IPN) were prepared by combining chitosan (CS) and ionic liquid-based polymers and copolymers, namely poly(1-butyl-3-vinylimidazolium chloride) (poly(BVImCl)) and poly(2-hydroxymethyl methacrylate-co-1-butyl-3-vinylimidazolium chloride) (poly(HEMA-co-BVImCl)). Results show that prepared semi-IPNs presented high mechanical stability and were positively charged over a broad pH range, including basic pH. Semi-IPNs also presented faster permeation and release rates of lidocaine hydrochloride (LH), under external electrical stimulus (0.56 mA/cm2) in aqueous media at 32 °C. The kinetic release constants and the LH diffusion coefficients measured under electrical stimulus were ~1.5 and > 2.7 times higher for those measured for passive release. Finally, both semi-IPNs were non-haemolytic (haemolytic index ≤0.2%) and showed strong haemostatic activity (blood clotting index of ~12 ± 1%). Altogether, these results show that the prepared polycationic semi-IPN hydrogels presented advantageous mechanical, responsive and biological properties that enable them to be potentially employed for the design of new, safer, and advanced stimuli-responsive biomaterials for several biomedical applications such as haemostatic and wound healing dressings and iontophoretic patches.

Iontophoretic skin delivery systems: Success and failures.

Iontophoretic transdermal delivery uses a small electric current to push charged molecules into the skin under an electrode of same polarity and offers an attractive option to facilitate the delivery of macromolecules or hydrophilic molecules and to improve patient compliance. This technique has been used in physical therapy clinics for several decades, though the science was not always there to support claims of clinical effectiveness. Recently, this modality of treatment has undergone more systematic and rigorous investigations to withstand the scrutiny of regulatory authorities. In recent years various drugs have gained FDA approval for iontophoretic patches. This technique is gaining recognition due to better compliance rates, non-invasive drug delivery leading to fewer side effects, and sustained release of the drug. Furthermore, programmed delivery and bolus delivery systems have helped with customizing the drug dosage and frequency of dosage based on the patient's need.

Transdermal Delivery of Nanoparticles Using Microneedles and Iontophoresis (P13-001-19)

ObjectivesMicroneedles (MN) and iontophoresis are innovative approaches for transdermal delivery of drugs and bioactive compounds. They can make the treatment tolerable, safe, and convenient. Nanoparticles (NPs) can enhance solubility, stability and prolonged release of many drugs and bioactive compounds and deliver them to specific cells. In the present study, we determined the delivery efficacy of dye-loaded lipid NPs using MN, iontophoresis and their combination, in an in vitro skin permeation study. MethodsWe have synthesized lipid NPs carrying 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N- (lissamine rhodamine B sulfonyl (Rhod PE) dye. MN derma skin rollers with different needle length were used for microneedling. Iontophoresis was applied using a patch and a constant-current power supply. The abdominal skin of porcine was initially treated by the MN derma roller and then topically treated with NP solutions. In the combined treatment (MN and iontophoresis); the NP solution was loaded into an iontophoretic patch and applied on the MN-treated skin for 2, 4, 6, 12 and 24 hours at 0.2 mA/cm2. Non-treated skin (no MN or iontophoresis) was used as a control group. Fluorescent dye intensity in different skin layers were examined using a fluorescence microscopy. ResultsThe penetration of fluorescent dye through the skin layers was increased and reached to the subcutaneous adipose tissue following increment of MN length (1.5 mm > 1 mm > 0.5 mm), time and combined treatments. Combination of MN and iontophoresis resulted in increased dye intensity in the dermis and subcutaneous adipose tissue over time. ConclusionsThe combination of MN and iontophoresis can enhance subcutaneous delivery of drugs and bioactive compounds, along with enhanced efficacy and patient compliance, and reduced toxicity. We envision that combination of MN and iontophoresis could offer a clinical superiority over traditional, invasive injections for combating diseases and disorders. Funding SourcesNIH (Grant R15AT008733).

Transdermal iontophoretic delivery of tacrine hydrochloride: Correlation between in vitro permeation and in vivo performance in rats

The aim of present investigation is to evaluate the feasibility of transdermal iontophoretic delivery of tacrine hydrochloride in Sprague Dawley (SD) rats using anodal iontophoretic patches and to correlate plasma tacrine concentration profiles to in vitro tacrine permeation flux. In vitro skin permeation studies were carried out across artificial membrane CELGRAD® 2400, freshly excised SD rat abdominal skin, freshly excised hairless rat abdominal skin, and frozen pig skin to examine the role of permeation membranes. Furthermore, plasma profiles with an application of 0.1–0.3mA current strength and tacrine concentration loading of 5–20mg/ml were obtained in SD rats. The tacrine plasma profiles were fitted to one-compartmental model using WinNonlin and in vivo transdermal absorption rates were then correlated to in vitro permeation profiles using various approaches. Tacrine permeation across membranes revealed current dependent interspecies differences at lower current strength application which diminished at higher current strength application, whereas, no significant difference in tacrine permeation was observed across fresh and frozen SD rat skin under 0.2mA current application. In vivo studies confirmed current and concentration dependent tacrine plasma profiles with possible tacrine depot formation under the skin in-line with earlier in vitro results. Correlation of in vivo transdermal absorption rates to in vitro permeation profiles revealed higher in vitro permeation fluxes compare to in vivo transdermal absorption rates at varied combination of current strength and concentrations. Present in vivo studies support the earlier published in vitro findings and tacrine plasma profiles show a potential to reach therapeutic effective concentration of tacrine hydrochloride to provide a platform for pre-programmed tacrine delivery.

Sumatriptan iontophoretic transdermal system for acute treatment of episodic migraine

ABSTRACTMigraine is a common and debilitating condition affecting approximately nearly one in four women in the USA and Europe. Episodic attacks can be associated with a number of symptoms, with nausea and/or vomiting being among the most frequent and distressing. Sumatriptan is widely used for acute treatment of migraine and is available in several formulations. The efficacy of oral sumatriptan is well-established. However, patients who experience migraine-associated nausea and/or vomiting can have difficulty swallowing tablets and may delay taking anti-migraine medication. In addition, absorption of oral sumatriptan can be reduced by migraine-associated gastroparesis. Non-oral formulations of sumatriptan are recommended for patients with nausea and/or vomiting, but their use may be limited by adverse effects and patient acceptance. A new transdermal formulation of sumatriptan has recently become available in the USA for acute treatment of migraine in adults. In this article, we review the properties of the sumatriptan iontophoretic transdermal patch and discuss the evidence to support its use in clinical practice.

Update on future headache treatments

Headache disorders are common and heterogenous neurologic entities. The complexities of management are further encumbered by the relatively few effective choices for acute and preventive therapies available to the headache specialist to treat these diverse disorders. As advances have been made in uncovering headache pathophysiology, new therapies have surfaced and others are forthcoming. This article will highlight new lines of care in development. There are several novel delivery mechanisms of familiar medications which bypass the limitations of current delivery systems, including the sumatriptan iontophoretic patch Zecuity, the intranasal sumatriptan OptiNose system, the zolmitriptan Rapidfilm orally dissolvable film and the orally inhaled dihydroergotamine Levadex system. New lines of care based upon recently discovered therapeutic targets will also be discussed including calcitonin gene-related peptide (CGRP) receptor antagonists, serotonin receptor agonists, and sphenopalatine ganglion (SPG) intermittent stimulation. Finally, emerging targets for future therapeutics will be explored including transient receptor potential vanilloid (TRPV1) receptor modulators, nitric oxide (NO) antagonists, gap junction modulators, glutamate receptor antagonists, orexin receptor antagonists and prostanoid receptor antagonists. Therapies developing over the next several years will be welcome additions to the headache specialist's armamentarium.

Transdermal Delivery Using a Novel Electrochemical Device, Part 2: In Vivo Study in Humans

A single-center, open-label, and dose-escalation clinical trial has been performed using a novel electrochemical transdermal patch comprising a drug-loaded hydrogel sandwiched between two silver electrodes. The lower electrode is attached flatly to skin via an adhesive layer. This noniontophoretic device produces flux enhancement via voltage-induced electrolysis of the water in the hydrogel. A voltage application of 2 V over 60 s produced release of approximately 315 to 340 μg of fentanyl from a patch. A single-voltage application at t = 16 h produced a maximum plasma level of approximately 200 pg/mL before patch removal at t = 41 h. Consecutive voltage applications at t = 16 h and t = 40 h produced a maximum plasma level of approximately 730 pg/mL. The lag time between voltage application and achievement of a plasma profile plateau is longer than that reported for an iontophoretic patch. The patch's advantage is production of an on-demand plasma profile without the use of potentially irritating iontophoresis. In contrast to a passive transdermal system, it is possible to adjust the plasma profile by using voltage application. It is not necessary to apply a continual current, in contrast to iontophoretic systems.

The therapeutic future in headache

There are many categories and individual types of headache and most have a variety of treatment protocols, while a few are best treated by just one medication. This paper will concentrate on acute care medications for migraine and discuss some new and future acute care treatments. There is not much to discuss about prevention, except that onabotulinumtoxinA has been approved for prevention of chronic migraine. Cluster headache will also be discussed, as there are some future treatments for acute care and prevention being studied at present. For the acute care of migraine in the US, we have seven triptans by tablet plus other routes and one non steroidal anti-inflammatory medication approved by the FDA that is currently available (Cambia brand of buffered diclofenac potassium for oral solution). There are several other acute care medications in various stages of development and there are three new methods of administering a triptan and others under investigation. The optimal acute care therapy for migraine should be faster, easier to use and more efficient with fewer adverse events than what is currently available. What follows is a brief review of the status in development for five of the many new acute care medications being investigated: the CGRP antagonist tablet telcagepant, the sumatriptan iontophoretic patch Zelrix, sumatriptan powder for use in the OptiNose apparatus, dihydroergotamine for oral inhalation (Levadex), civamide nasal solution for prevention of episodic cluster headache (Civanex) and sphenopalatine ganglion stimulation for acute cluster attacks in chronic cluster headaches. Other future treatments that will not be discussed include transcranial magnetic stimulation, a 5-HT(1F) agonist named alniditan, large conductance calcium-activated potassium channel openers, glial modulators or other medications and devices in early stages of development.

Sumatriptan transdermal iontophoretic patch (NP101-Zelrix™): review of pharmacology, clinical efficacy, and safety in the acute treatment of migraine.

Migraine is a chronic, painful, and often disabling primary headache disorder, typically presenting with recurrent attacks that may be accompanied by a variety of neurological, gastrointestinal, and autonomic symptoms. Gastrointestinal symptoms in association with migraine including, nausea, vomiting, and gastroparesis, affect a large proportion of migraine sufferers. These symptoms may result in delays or inconsistencies in the absorption of oral treatments. Hence, the necessity for an innovative, non-invasive, parenteral delivery formulation for quick and effective treatment of migraine attacks is evident. Iontophoresis utilizes minimal amounts of electrical potential to support the fast transfer of ionized medication transdermally and into the general circulation. Two pharmacokinetic clinical trials have shown that iontophoretic delivery of sumatriptan through the skin produces quick and reproducible therapeutic plasma concentrations. A randomized, double-blind, multicenter, phase III study demonstrated superior efficacy versus placebo and excellent tolerability, with no triptan-related adverse events. The proportion of patients that were pain-free at 2 h post-treatment was 18% for the sumatriptan patch vs 9% for placebo (P = 0.0092; number needed to treat = 11.1). Upon approval from the Food and Drug Administration and other regulatory authorities, the iontophoretic transdermal delivery of sumatriptan will be a good choice for patients experiencing poor absorption of oral medication often associated with migraine and/or for those with intolerable triptan-related adverse events.

In vitro and in vivo transdermal iontophoretic delivery of naloxone, an opioid antagonist

The feasibility of transdermal delivery of naloxone, an opioid antagonist, by anodal iontophoresis patches using Ag/AgCl electrodes was investigated. To examine the effect of current strength, species variation and drug concentration on skin permeability of naloxone, in vitro skin permeation studies were performed using rat dorsal skin and porcine ear skin as the membrane. To determine in vivo transdermal absorption rate of naloxone, the iontophoretic patch system was applied to the dorsal skin of conscious rat with a constant current supply for 24h. The in vitro steady-state skin permeation flux of naloxone current-proportionally (0-360 μA/cm(2)) increased without significant differences between these two different skin types. The in vitro delivery rate through the porcine skin was found to be independent of the concentration of naloxone hydrochloride dehydrate in the donor patch over the range from 1 to 10% (w/v). In the in vivo pharmacokinetic study, plasma concentrations of naloxone steadily increased and sustained steady-state levels from 4h to 24h after the initiation of current application. In vivo steady-state transdermal absorption rates at 90 and 180 μA/cm(2) were 136 and 305 μg/h/cm(2), respectively. These results suggest that the transdermal delivery rates of naloxone by anodal iontophoresis are sufficient for the management of intoxication in opioid-overdosed patients.

In-vitro and in-vivo transdermal iontophoretic delivery of tramadol, a centrally acting analgesic

The feasibility of transdermal delivery of tramadol, a centrally acting analgesic, by anodal iontophoresis using Ag/AgCl electrodes was investigated in vitro and in vivo. To examine the effect of species variation and current strength on skin permeability of tramadol, in-vitro skin permeation studies were performed using porcine ear skin, guinea-pig abdominal skin and hairless mouse abdominal skin as the membrane. In an in-vivo pharmacokinetic study, an iontophoretic patch system was applied to the abdominal skin of conscious guinea pigs with a constant current supply (250 µA/cm(2)) for 6 h. An intravenous injection group to determine the pharmacokinetic parameters for estimation of the transdermal absorption rate in guinea pigs was also included. The in-vitro steady-state skin permeation flux of tramadol current-dependently increased without significant differences among the three different skin types. In the in-vivo pharmacokinetic study, plasma concentrations of tramadol steadily increased and reached steady state (336 ng/ml) 3 h after initiation of current supply, and the in-vivo steady-state transdermal absorption rate was 499 µg/cm(2) per h as calculated by a constrained numeric deconvolution method. The present study reveals that anodal iontophoresis provides current-controlled transdermal delivery of tramadol without significant interspecies differences, and enables the delivery of therapeutic amounts of tramadol.

New frontiers in headache therapy

There are numerous headache therapies available for our patients, more for migraine than for any of the other primary headache disorders. Only four medications have been approved for migraine prevention in the last few decades in the US and onabotulinumtoxinA was recently approved in the UK and the US for chronic migraine. We have been more fortunate in the acute care arena where in the US we have had seven triptans and one nonsteroidal anti-inflammatory medication approved by the FDA and currently available. There are several other acute care medications in various stages of development and there are two new methods of administering a triptan and others under investigation. We are always looking for faster, easier and more efficient administration of medications with fewer adverse events, as optimal migraine therapy requires these characteristics. What follows is a brief review of the progress in development for four of the many new acute care medications being investigated: the CGRP antagonist tablet telcagepant, the sumatriptan iontophoretic patch, sumatriptan powder for use in the OptiNose apparatus and the dihydroergotamine oral inhaler. I will not include transcranial magnetic stimulation, a 5-HT(1F) agonist, large conductance calcium-activated potassium channel openers, glial modulators or other medications and devices in early stages of development [1].

Non-invasive iontophoretic delivery of peptides and proteins across the skin

Introduction: Peptides and proteins are playing an increasingly important role in modern therapy. Their potency and specificity make them excellent therapeutic agents; however, their physicochemical properties and stability requirements almost invariably necessitate their administration by subcutaneous, intramuscular or intravenous injection. Controlled non-invasive administration using more patient-friendly advanced delivery technologies may combine the precision afforded by parenteral administration with improved compliance and the potential for individualized therapy.Areas covered: Transdermal iontophoresis enables hydrophilic charged molecules to be administered through the skin in an effective, non-invasive, patient-friendly manner. This review presents the basic concepts and an analysis of the effect of iontophoretic parameters and molecular properties on electrotransport rates across the skin along with a summary of experimental studies with peptides and proteins. The last section covers other techniques used in conjunction with iontophoresis.Expert opinion: It has long been known that iontophoresis can administer therapeutic amounts of biologically active peptides into the body. More recent studies have shown that it is also capable of delivering structurally intact, functional proteins non-invasively into and across intact human skin. The next step is to develop cost-effective and easy-to-use iontophoretic patch systems that ensure biomolecule stability, optimize delivery efficiency and address unmet therapeutic needs.

New acute treatments for headache

Although we have several acute care medications for the treatment of migraine, we are always looking for new medications to treat our patients. Patients often say that their headaches are not under optimal control and would be happy to try another medication. Patients look for faster onset of relief, more complete relief, no recurrent headache and no adverse events. This article will cover some new and some anticipated acute care products, CGRP antagonists, sumatriptan by iontophoretic patch, sumatriptan by needle-free injections, DHE by oral inhalation and diclofenac potassium in a sachet. Botulinum toxin therapy, although a preventive measure, will be mentioned at the end.