Transdermal iontophoresis current density

Nugroho, A.K., et al. 2004. Transdermal iontophoresis of rotigotine Influence of concentration, temperature and current density in human skin in vitro. J Control Release 96 159. 

For current densities at or above 0.2mA/cm, the sensation associated with transdermal iontophoresis is determined by the type of ion being delivered into the skin. When human subjects compared the sensation experienced during iontophoresis of different salt solutions applied to the right and left forearms, delivery of calcium caused less sensation than delivery of phosphate, magnesium, and zinc, which caused less sensation than delivery of chloride, acetate, citrate, and sulfate, which in turn caused less sensation than delivery of lithium, potassium, and sodium. In general, multivalent ions were found to cause less sensation than monovalent ions. ... 

Gyory, J.R. Phipps, J.B. Effect of current density and current duration on the membrane resistance of skin. In Transdermal Administration, A Case Study, Iontophoresis, APGI/CRS European Symposium, Couvreur, P., Duchene, D., Green, P., Junginger, H.E., Eds. 3-4 March 1997 Paris, France Editions de Sante Paris, 1997 262-265. 

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