The usual dose in adults is 5 mg four times a day for until diarrhea is controlled, followed by 2.5 mg up to four times daily as needed. Diphenoxylate with atropine is available as tablets 2.5 mg of diphenoxylate with 0.025 mg of atropine and as a solution of similar concentration in 5 mL generically and under the brand name Lomotil. Diphenoxylate in combination with atropine was approved for use in the United States in 1960 and is still widely used to treat acute infectious and nonspecific diarrhea caused by gastroenteritis. Typically, low doses of atropine are added to diphenoxylate to prevent abuse and excessive intake. Diphenoxylate acts as a potent opiate agonist in the intestine and reduces intestinal motility, causing a slowing of intestinal transport and increased resorption of water and electrolytes, actions that are helpful in treating diarrhea. Diphenoxylate is similar to loperamide and is not structurally related to morphine or codeine, and has minimal euphoric or analgesic effects, largely because it is given in low doses and in fixed combination with atropine. Diphenoxylate (dye” fen ox’ i late) is a synthetic piperidine derivative that acts as a mild opiate receptor agonist (predominant µ type receptors), but is used largely for the treatment of diarrhea rather than pain.

Diphenoxylate atropine antidote