Laxative abuse syndrome

Abuse/Dependency Chronic use of laxatives, particularly stimulants, may lead to laxative dependency, which in turn may result in fluid and electrolyte imbalances, steatorrhea, osteomalacia, vitamin and mineral deficiencies, and a poorly functioning colon. Also known as laxative abuse syndrome (LAS), it is difficult to diagnose. Cathartic colon Cathartic colon, a poorly functioning colon, results from the chronic abuse of stimulant cathartics. 

The determination of laxative abuse syndrome can be difficult because many laxative abusers vigorously deny laxative use. Middle-aged women tend to be the most common laxative abusers. The chronic laxative abuse problem should be addressed by a combination of measures, including psychiatric evaluation, dietary modification with reliance on bulk-forming laxatives, and specific guidelines to the patient for the withdrawal of stimulant laxatives. 

It is recommended that stimulant laxatives should not be used for more than 2 weeks because long-term use may cause inflammation of the mucous membranes and pigmentation of the colon (pseudomelanosis coli) which is reversible after use is stopped. There is the risk of the well-known laxative abuse syndrome, particularly in anorexia nervosa and in bulimia. This leads to diarrhoea, disturbance of electrolyte and water balance... 

Noninfectious causes of acute diarrhea include drugs and toxins (Table 18-3), laxative abuse, food intolerance, irritable bowel syndrome (IBS), inflammatory bowel disease, ischemic bowel disease, lactase deficiency, Whipple s disease, pernicious anemia, diabetes mellitus, malabsorption, fecal impaction, diverticulosis, and celiac sprue. 

Chronic diarrhea lasts for longer than 4 weeks. Most cases result from functional or inflammatory bowel disorders, endocrine disorders, malabsorption syndromes and drugs (including laxative abuse). In chronic diarrhea, daily watery stools may not occur. Diarrhea may be either intermittent or persistent. 

Laxative abuse includes symptoms of abdominal pain, weakness, fatigue, thirst, vomiting, edema, bone pain, fluid and electrolyte imbalance, hypoalbuminemia, and syndromes that mimic colitis. 

Habitual, usually secretive, abuse of laxatives is much more common in women than in men and there is overlap with the anorectic/bulimic sjmdrome. Abuse of irritant agents such as senna and cascara have been the commonest varieties (SED-10, 704), but many proprietary laxatives have been abused. Abuse can lead to a condition characterized by chronic diarrhea, hjq)okalemia, and fluid depletion. The features also include hjq)omagnesemia, hjq)ocalcemia, and hjq)oalbuminemia, with thirst, lassitude, weight loss, edema, and occasionally osteomalacic bone pain and clubbing. In one small series of cases of laxative abusers, pseudo-Bartter s syndrome was induced the com-phcations included confusion, convulsions, muscle weakness (with or without paralysis or rhabdomyolysis), and... 

Meyers AM, Feldman C, Sonnekus MI, Ninin DT, MargoUus LP, WhaUey NA. Chronic laxative abusers with pseudo-idiopathic oedema and autonomous pseudo-Bartter s syndrome. A spectrum of metabolic madness, or new lights on an old disease S Afr Med J 1990 78(11) 631-6. 

Siegel, R. 1979. Ginseng abuse syndrome Problems with the panacea. JAMA 241, 1614-1615. Siegers, C. 1992. Anthranoid laxatives and colorectal cancer. Trends Pharmacol. Sci. 13, 229-231. Simpson, E., Law, S., and Storrs, F. 2004. Prevalence of botanical extract allergy in patients with contact dermatitis. Dermatitis 15, 67-72. 

FIGURE 36-2. Recommendations for treating chronic diarrhea. Follow these steps (1) Perform a careful history and physical examination. (2) The possible causes of chronic diarrhea are many. These can be classified into intestinal infections (bacterial or protozoal), inflammatory disease (Crohn s disease or ulcerative colitis), malabsorption (lactose intolerance), secretory hormonal tumor (intestinal carcinoid tumor or VIPoma), drug (antacid), factitious (laxative abuse), or motility disturbance (diabetes mellitus, irritable bowel syndrome, or hyperthyroidism). (3) If the diagnosis is uncertain, selected appropriate diagnostic studies should be ordered. (4) Once diagnosed, treatment is planned for the underlying cause with symptomatic antidiarrheal therapy. (5) If no specific cause can be identified, symptomatic therapy is prescribed. 

Misconceptions about normal bowel patterns and the effect of laxatives have contributed to a syndrome of laxative abuse that is relatively common in the United States. The availability of laxatives as chocolates or gums conveys to the public that the use of these agents is without adverse consequences. Abuse of laxatives has occurred traditionally in persons trying to maintain daily bowel function, but more recently has extended to others who use laxatives for the purpose of controlling weight. In either case, the consistent abuse of strong laxatives and cathartics may lead to serious illness. 

Hypomagnesemia is usually associated with disorders of the intestinal tract or kidney. Drugs or conditions that interfere with intestinal absorption or increase renal excretion of magnesium can result in hypomagnesemia (Table 50-6). Decreased intestinal absorption as a result of small bowel disease is the most common cause of hypomagnesemia worldwide. These disorders include regional enteritis radiation enteritis ulcerative colitis acute and chronic diarrhea pancreatic insufficiency and other malabsorptive syndromes small-bowel bypass surgery and chronic laxative abuse. ... 

Chronic diarrhea may be due to laxative abuse, lactose intolerance, inflammatory bowel disease, malabsorption syndromes, endocrine disorders, irritable bowel syndrome and other disorders. Treatment with nonspecific antidiarrheal agents such as those listed in Table 6.2 may mask an underlying disorder. Treatment of chronic diarrhea should be aimed at correcting the cause of diarrhea rather than alleviating the symptoms. 

Diarrhea is defined as frequent liquid stools that can be caused by foods, fecal impaction, bacteria Escherichia coli, Salmonella), virus parvovirus, rotavirus), toxins, drug reaction, laxative abuse, malabsorption syndrome caused by lack of digestive enzymes, stress and anxiety, bowel tumor, and inflammatory bowel disease such as ulcerative colitis or Crohn s disease. 

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