The risks of acupuncture are low if you have a competent, certified acupuncture practitioner. Possible side effects and complications include:
Soreness. After acupuncture, you might have soreness, minor bleeding or bruising at the needle sites.
Organ injury. If the needles are pushed in too deeply, they could puncture an internal organ — particularly a lung. This is an extremely rare complication in the hands of an experienced practitioner.
Infections. Licensed acupuncturists are required to use sterile, disposable needles. A reused needle could expose you to diseases, such as hepatitis.
Not everyone is a good candidate for acupuncture or for particular types of acupuncture. Conditions that may increase your risks of complications include:
Bleeding disorders. Your chances of bleeding or bruising from the needles increase if you have a bleeding disorder or if you’re taking blood thinners, such as warfarin (Coumadin), so let your acupuncturist know.
Having a pacemaker. Acupuncture that involves applying mild electrical pulses to the needles can interfere with a pacemaker’s operation.
Being pregnant. Some types of acupuncture are thought to stimulate labor, which could result in a premature delivery.