The U.S. Food and Drug Administration lists 125 items with medical shortages, ranging from an asthma drug to vials of sterile water at certain sizes. The ones that affect the most people are shortages of Adderall, which treats attention deficit hyperactivity disorder, and the antibiotic amoxicillin, said Dr. Kelsey Schwander, a clinical pharmacist at the University of Colorado Anschutz medical campus.