Who knew? Calcium, the fabled bone-builder, turns out to have another benefit: It’s a bullish butt-plug—at least for diarrhea associated with nelfinavir (Viracept). The innovation came about through the willingness of Enrique Perez-Rodriguez, MD, to listen to a patient who swore that the runs stopped when he started taking calcium for an unrelated reason. So the San Antonio, Texas, doc began a study of 500 milligrams (mg) of calcium given twice daily to 24 patients with nelfinavir-related diarrhea treated unsuccessfully with at least one antidiarrheal med. Prior to the calcium, diarrhea was mild in 40 percent, moderate in 47 percent and severe in 13 percent. After at least 48 hours of calcium therapy, every patient reported fewer and/or firmer stools, and more than two-thirds (67 percent) reported normal stools. Perez-Rodriguez says that the operative mechanism remains to be discovered, but since 1,000 mg of calcium is a nontoxic, standard daily dose, he’s just happy it’s helping.