This study presents the adverse effects of acupuncture as recorded in the Medline database for the years 1981-1994. A total of 125 papers were localized by the keywords acupuncture adverse effects. Articles without case reports were excluded, and 78 reports forms the basis for the present paper. A total of 193 patients were reported with adverse effects of acupuncture in 14 years. Pneumothorax is the most common mechanical organ injury, while hepatitis dominates among infections. Acupuncture treatment is claimed to be responsible in the death of three patients. One patient died from bilateral pneumothorax, another got endocarditis, and died of complications. The third patient died of severe asthma while under acupuncture treatment. Most adverse effects of acupuncture seem to rely on insufficient basic medical knowledge, low hygienic standard, and inadequate acupuncture education. The study confirms the adverse effects of acupuncture under certain circumstances. Serious adverse effects, however, are few, and acupuncture can generally be considered as a safe treatment.