A transdermal drug delivery device e.g. microneedle, comprises needles 10 or other means for piercing the skin 4 of a patient to form pores 20 in a predefined pattern； and carriers 12 in the same pattern that may be loaded with a drug 14 for delivery. Means are provided for superposing the carriers 12 on the pores 20 to deliver the drug 14 through the pores 20 to a location beneath the surface of the skin 4. The carriers 12 may remain outside the pores 20, be introduced into the pores 20 after the needles 10 have been removed or be inserted alongside the needles 20 while they are still in place.
