Is it just a placebo?

No. Studies have shown that there are cellular changes as well as reactions in the brain due to acupuncture. Also, acupuncture has been widely used to treat a variety of domestic animals, especially cats, dogs and horses. These animals are not susceptible to the placebo effect and to the psychosomatic element of therapy. This means that it is the insertion of needles into specific points, itself, that works.

Any form of medicine has a placebo component, including modernWestern medicine. The placebo effect is just a small part of acupuncture's effectiveness. While a positive attitude may enhance healing, a negative attitude will not block the effects of acupuncture.