Chelation therapy is among the safest medical procedures. More than 400,000 patients have received over four million treatments during the past 30 years. Not one death has been directly caused by chelation therapy when properly administered by a physician who was fully trained and competent in the use of this therapy. Side effects are possible, as with any drug therapy. Vein irritation, mild pain, headache, and fatigue may occur. Occasionally a mild and transient fever occurs. These and other minor side effects, if they occur, are easily controlled by adjusting the duration and frequency of treatment, or with the use of other simple measures. Side effects tend to diminish after the first few treatments. Most patients experience few or no side effects.