Infection is an extremely rare consequence of acupuncture treatment. There have been only two reported incidences of hepatitis transmission in the U.S. literature, both cases were due to the use of unsterilized needles. Acupuncture needles are stainless steel and should be sterile. Care should be taken not to insert the needle through areas of cellulitis. Sterile skin preparation is only necessary for deep needling of the ear, groin, or rectal areas.
Pneumothorax is an infrequent complication.
Deep needling of the thoracic cage and hilar areas is discouraged. The small size of the acupuncture needles makes a significant pneumothorax unlikely in any case. While ecchymosis are occasionally seen, significant hematoma are not. This is probably because of the torpedo shape of an acupuncture needle, as opposed to the beveled cutting edge of a hypodermic needle. The needle shape is probably also responsible for the lack of enduring damage to nerves or other tissues and structures.