Iontophoresis-activated drug

Magnetics-activated drug delivery systems Sonophoresis-activated drug delivery systems Iontophoresis-activated drug delivery systems Hydration-activated drug delivery systems... 

Transdermal delivery is suitable for small, generally lipophilic, potent molecules that require low input rates to achieve effective plasma concentrations. There may be a slow rate of increase of concentration if the drug forms a depot in the skin. Depot formation will also result in a slow decrease in concentration when the system is removed from the skin. These disadvantages can be overcome by the use of iontophoresis, by which the molecules are actively carried across the skin by a small electrical current. This provides a faster and more controllable transfer of drug. Intramuscular/Subcutaneous... 

For other routes of delivery, the formulation considerations relating to polymers are less restrictive than for the parenteral route. Typically, for local rather than systemic activity, polymers can be used to enhance efficacy of topical drug delivery systems through solubility enhancement and or skin hydration. For transdermal delivery, polymers can have several roles, either as solubility modifiers, permeation enhancers or as aids in iontophoresis. The presence of multiple-charged species is a prerequisite for iontophoretic movement of drag molecules through the skin, so can be considered as an actuation process... 

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