Paralytic ileus associated with use of diltiazem

A case of paralytic ileus in a patient receiving oral diltiazem therapy for atrial fibrillation is reported.

A 64-year-old man with a history of multiple serious comorbidities, poly-pharmacy, and a recent hospital stay for acute cardiac problems was readmitted to the hospital for gastrointestinal (GI) bleeding. On day 2 of the readmission, he suffered a myocardial infarction complicated by atrial fibrillation with a rapid ventricular response. After initial treatment with oral metoprolol for ventricular rate control was discontinued (due to ineffective rate control and patient complaints of respiratory symptoms), oral diltiazem hydrochloride therapy (30 mg every six hours) was initiated on day 7; the dose was adjusted to a maximum of 120 mg every six hours on day 10. On day 12, the patient complained of nausea, abdominal pain and tenderness, and infrequent bowel movements; imaging studies on day 13 indicated paralytic ileus. Pursuant to a surgical consultation, a nasogastric tube was inserted and nothing was given by mouth except medications. After initial improvement of the GI symptoms, the feeding tube was removed; however, the symptoms worsened over the next two to three days, requiring reinsertion of the tube on day 16. On day 18, after other potential causes of ileus were ruled out, diltiazem therapy was withdrawn. The man experienced rapid symptomatic improvement, with no further GI symptoms, and was discharged four days later.

A 64-year-old man receiving high-dose diltiazem to treat atrial fibrillation developed paralytic ileus, which quickly resolved after the medication was discontinued.