Intravenous chelation (pronounced key-LAY-shun) therapy has been a respected and widely used medical treatment for heavy-metal poisoning–especially lead poisoning–for more than 50 years. However, some physicians also promote the therapy as an alternative treatment for arteriosclerosis (hardening of the arteries), including coronary artery disease, peripheral vascular disease (blockage or narrowing of blood vessels in the legs), and the mental deterioration caused by small strokes.