Distal esophageal obstruction due to a guar gum preparation (Cal-Ban 3000).

Guar gum is a high polymer carbohydrate that undergoes considerable expansion and thickening when placed in water. Because of this property, guar gum has been used in "weight loss" tablets marketed by several pharmaceutical manufacturers. These tablets undergo expansion in the stomach and are expected to cause early satiety. Patients with esophageal disorders should be cautioned against the use of this product because it may expand in the esophagus and create an obstruction.