Hate getting shots at the doctor? Take heart: scientists are working on microscopic needles that don't hurt. First up, vaccines:
Microneedle patches are about the size of a postage stamp and hold hundreds of miniscule needles, each less than a millimeter long. They feel "like 400-grit, fine sandpaper," says Pete Daddona, chief scientific officer at Zosano Pharma Inc., in Fremont, Ca., which is working on microneedle delivery for several drugs, including one for treating osteoporosis.
Though skin is approximately 2 millimeters thick, the outermost barrier is much thinner. Once through it, the microneedles are within the skin's wet interior, where vaccines can reach the immune system and medicines can easily get into the bloodstream.