Sodium phosphate enemas are used in the treatment of constipation and for preparation for flexible sigmoidoscopy. Sodium phosphate enema use in older adults (mean age 80 years, range 61 to 89 years) is associated with hypotension, volume depletion, hyperphosphatemia, hypo- or hyperkalemia, metabolic acidosis, severe hypocalcemia, renal failure and EKG changes (prolonged QT interval). In patients over the age of 70 years, use warm water enemas rather than sodium phosphate enemas.