Two types of Transdermal Delivery Systems exist on the market today:

  1. Reservoir System - the active drug is stored in a special compartment in the patch and released through a rate-controlling membrane
  2. Matrix System - the drug is released from a polymer matrix onto the skin where the rate of delivery is dependent on the rate of diffusion through the skin

The chart to the right
compares these
two systems:

 

Topic 3: Transdermal Delivery