A transdermal drug delivery device comprises needles (46,62) for piercing the skin (4) of a patient to form pores (44) in a predefined pattern; and carriers (40,82) in the same pattern that may be loaded with a drug (42) for delivery. Means are provided for applying the carriers (40,82) to the pores (44) while the needles (46,62) remain in the skin (4) to deliver the drug (42) through the pores (44) to a location beneath the surface of the skin (4).