Heat prostration can occur with drug use in the event of high environmental temperature. Diarrhea may be an early symptom of incomplete intestinal obstruction, especially in patients with ileostomy or colostomy; in this instance, treatment would be inappropriate and possibly harmful. This product may cause drowsiness or blurred vision. Patients taking this product should be warned not to engage in activities requiring mental alertness such as operating a motor vehicle or other machinery or to perform hazardous tasks while taking this drug.