Constipation is one of the most common digestive complaints in the general population. Over 2.5 million people consult a physician and hundreds of millions of dollars are spent on laxatives each year. Although constipation is often defined as a frequency of defecation twice weekly or less, constipated patients may complain of excessive straining with defecation, passage of hard or small stools, difficulty initiating evacuation, or a feeling of incomplete evacuation. Physicians should therefore not rely only on the criteria of defecation frequency when examining patients and managing constipation. TABLE. Laxatives Used in the Treatment of Constipation Laxatives Usual Adult Dose Onset of Action Bulk-forming laxatives Bran 2-4 tablespoons qd 12 to 72 h Methylcellulose 1 to 3 tbsp qd 12 to 72 h Psyllium 1 to 3 tbsp qd 12 to 72 h Calcium polycarbophi 2 to 4 tablets qid 24 to 48 h Osmotic agents Polyethylene glyco 17 g in 240 mL water 24 to 48 h Sorbito 15 to 30mLqd 24 to 48 h Lactulose 15 to 30mLqd 24 to 48 h Saline laxatives Magnesium Read more [...]

Bulk-Forming Laxatives Dietary fiber and bulk laxatives with adequate fluid intake are the most physiologic and safest of medical therapies. However, they may be counterproductive in patients with idiopathic slow transit constipation or with constipation associated with irritable bowel syndrome because they often worsen bloating and abdominal distension in these populations. Dietary Fiber Dietary fiber in cereals contain cell walls that resist digestion and retain water within their cellular structures, whereas those found in citrus fruits and legumes stimulate the growth of colonic flora and increase fecal mass. Wheat bran is the most effective fiber laxative with a clear dose response on fecal output. Patients with poor dietary habits may add 2 to 4 tablespoons of bran to each meal, followed by a glass of water or another beverage. A laxative effect may not be observed for 3 to 5 days. Patients should be cautioned that large amounts of bran can cause abdominal bloating or flatulence; therefore, they should start with small amounts and titrate slowly to the desired effect. Psyllium (Metamucil), Read more [...]

Chronic diarrhea is a frequent manifestation in patients with diabetes mellitus, and is present in patients with type 1 or type 2 diabetes. According to some evidence, up to 15% of patients with diabetes mellitus may experience diarrhea. However, other studies have found no difference in the prevalence of diarrhea between diabetics and community control subjects. Thus, in the general population there might be no increased prevalence or association between diarrhea and diabetes, and the symptoms of diarrhea might be attributable to other common conditions, such as irritable bowel syndrome (irritable bowel syndrome), occurring in a patient with diabetes. Nonetheless, some patients with diabetes have significant diarrhea and present for examination and treatment. Mechanisms of Chronic Diarrhea in Diabetes Mellitus Table Mechanisms, Concomitant Conditions,and Clinical Characteristics of Diarrhea in Diabetes Mellitus provides an overview of the pathophysiological mechanisms and conditions associated with diarrhea in diabetes. The mechanisms of chronic diarrhea in diabetes are incompletely understood. Read more [...]

Clinical Examination and Routine Tests An accurate clinical history should collect information on the stool form and the presence of urgency or incontinence. The chronic diarrhea of diabetes is generally watery, paroxysmal, and includes nocturnal episodes. Presence of blood per rectum, relationship of diarrhea to dietary factors including sorbitol-containing dietetic foods, and features suggestive of fecal incontinence should be sought in history. Oral medications used for glycemic control, such as metformin (Avandemet) and acarbose (Precose), are often associated with bloating, diarrhea, and other gastrointestinal side effects. Other medications may cause diarrhea, including laxatives and prokinetics. The clinical examination should include a thorough neurological evaluation, with the search for signs suggesting autonomic neuropathy (such as orthostatic hypotension, lack of pupillary response to light, response of pulse and blood pressure to the Valsalva maneuver and absence of sweating), or malabsorption, such as anemia, edema, and clubbing. The presence of an abdominal mass Read more [...]

When available, we recommend directing the therapeutic intervention to the relevant underlying mechanism of chronic diarrhea by the use of appropriate testing. We prefer this approach to sequential empiric trials with antidiarrheals and other trials (eg, with dietary alteration and antibiotics). Celiac Sprue If the clinical examination or routine laboratory tests are suggestive of malabsorption, further testing should be undertaken to identify potentially relevant conditions, specifically celiac sprue, bacterial overgrowth, and pancreatic exocrine insufficiency. Anti-endomysial and antitissue transglutaminase antibodies should be sought, and, eventually, a jejunal biopsy will be needed to confirm any positive serological findings. In patients with concomitant diabetes and celiac disease confirmed by jejunal biopsy, the institution of a gluten-free diet leads to the regression of mucosal abnormalities and typically normalizes bowel habits. There is a separate chapter on celiac. Gut Dysmotility and Hypersecretion The presence of gut dysmotility can be assessed by means of radiographic, breath Read more [...]

Severe C. difficile-Associated Diarrhea In patients with suspected C. difficile-induced diarrhea, the first priority is to discontinue the inciting antibiotic, if it is safe to do so. Up to 25% of all C. difficile infections will resolve spontaneously upon the discontinuation of antibiotics. However, patients with more severe symptoms should be treated with specific C. difficile-directed antibiotics. The two most commonly used agents are metronidazole and vancomycin. The advantages and disadvantages of each are described below. In addition to metronidazole and vancomycin, bacitracin, teicoplanin, fusidic acid and colestipol have been used to treat C. difficile infections. Metronidazole Metronidazole (250 to 500 mg given three to four times daily for 10 to 14 days) is now the first line agent for the treatment of C. difficile infection. It is less expensive and more readily available than vancomycin and is equally effective in terms of response (90%) and relapse (15 to 25%) rates. Metronidazole can be given either orally or intravenously. Oral metronidazole is well absorbed high in the gastrointestinal Read more [...]