Diarrhea, drug-induced

Diarrhea Drug related Antibiotic-induced bacterial overgrowth Hyperosmolar medications administered via feeding tubes Antacids containing magnesium Malabsorption Hypoalbuminemia/gut mucosal atrophy Pancreatic insufficiency Inadequate GIT surface area Rapid GIT transit Radiation enteritis Tube feeding related Rapid formula administration Formula hyperosmolalty Low residue (fiber) content Lactose intolerance Bacterial contamination... 

Hepatitis In 1 retrospective study of 7492 patients on rapidly absorbed aminosalicylic acid preparations, drug-induced hepatitis occurred in 38 patients (0.5%) in these 38, the first symptom usually appeared within 3 months of the start of therapy with a rash as the most common event followed by fever and much less freguently by Gl disturbances of anorexia, nausea, or diarrhea. 

Diarrhea is a common problem that is usually self-limiting and of short duration. Increased accumulations of small intestinal and colonic contents are known to be responsible for producing diarrhea. The former may be caused by increased intestinal secretion which may be enterotoxin-induced, eg, cholera and E. col[ or hormone and drug-induced, eg, caffeine, prostaglandins, and laxatives decreased intestinal absorption because of decreased mucosal surface area, mucosal disease, eg, tropical spme, or osmotic deficiency, eg, disaccharidase or lactase deficiency and rapid transit of contents. An increased accumulation of colonic content may be linked to increased colonic secretion owing to hydroxy fatty acid or bile acids, and exudation, eg, inflammatory bowel disease or amebiasis decreased colonic absorption caused by decreased surface area, mucosal disease, and osmotic factors and rapid transit, eg, irritable bowel syndrome. 

Despite the lack of studies correlating the antidiarrheic activity of crude drugs with the presence of flavonoids, these have been also studied as pure compounds in this regard. The most used assay of antidiarrhoeic activity is the castor oil test, in which diarrhea is induced by the oral administration of castor oil to mice. Different flavonoids have been shown to possess antidiarrheal activity in this test quercetin, kaempferol, morin, myricetin, rutin (i.p.) [117,118], quercitrin (p.o.) [114,119], and tematin (i.p.) [44], all showing a dose-dependent activity in the range between 25 and 100 mg/kg. However, flavonoids are not only able to exert a preventive antidiarrheal effect in this acute model of experimentally-induced diarrhea, but also in chronic models. Thus quercitrin showed beneficial effects in a model of lactose-induced chronic diarrhea in rats, since it reduced the diarrheal output and facilitated colonic mucosal repair in lactose fed [120]. 

The side effects of mycophenolate mofetil include diarrhea, abdominal pain, constipation, nausea/vomiting, acne, dyspnea, cough, peripheral edema, increased risk of infections, drug-induced fever, dizziness, headaches, leukopenia and anemia. 

HIV patients These immunocompromised patients with Pneumocystis pneumonia frequently show drug-induced fever, rashes, diarrhea and/or pancytopenia. 

Adding mirtazapine s 5FIT3 antagonism to venlafaxine or SSRIs may reverse drug-induced nausea, diarrhea, stomach cramps, and gastrointestinal side effects... 

Nausea and vomiting are frequent, perhaps in as many as one-third of all cases. In about half the cases, diarrhea is induced or existing diarrhea aggravated. Melena can occur, but this seems unlikely to be drug-induced (SED-11, 594). 

Most adults consume about 25 g of lactose per day (500 mL of milk) without symptoms.When symptoms appear, they are usually mild and dose-related. The dose of lactose in most pharmaceuticals seldom exceeds 2 g per day. It is unlikely that severe gastrointestinal symptoms can be attributed to the lactose in a conventional oral solid-dosage form, especially in adults who have not previously been diagnosed as severely lactose-intolerant. However, anecdotal reports of drug-induced diarrhea due to lactose intolerance have been made following administration of pharmaceutical preparations containing lactose. 

Table 36-1 outlines the clinical presentation of diarrhea while Table 36-2 shows common drug-induced causes of diarrhea. A medication... 

Zafirlukast (and other -lukasts ) are antagonists at LTD4 receptors with slow onset of activity (see Figure VI-1 -4) used prophylactically for many forms of asthma, including antigen, exercise, or drug induced (e.g., ASA). Adverse effects include diarrhea, headache, and increased infections. 

Amoxaclllln (Table 38.5). Amoxicillin is a close analogue of ampicillin, in which a para-phenolic hydroxyl group has been introduced into the side-chain phenyl moiety. This adjusts the isoelectric point of the drug to a more acidic value, and this is believed to be partially responsible, along with the intestine peptide transporter, for the enhanced blood levels obtained with amoxicillin as compared to ampicillin itself (Table 38.6). Better oral absorption (74-92%) leads to less disturbance of the normal Gl flora and, therefore, less drug-induced diarrhea. The antimicrobial spectrum and clinical uses of amoxicillin are approximately the same as those of ampicillin itself, and it is presently one of the most popular drugs in North America. 

Diarrheal conditions may decrease drug absorption as a result of reduced intestinal residence time. The absorption of several drugs was decreased in response to lactose- and saline-induced diarrhea [145]. Digoxin absorption from tablets was impaired in one subject who developed chronic diarrhea as a result of x-ray treatment [146]. Abdominal radiation or the underlying disease has been shown to reduce digoxin and clorazepate absorption [147]. A dosage form that provides rapid drug dissolution (e.g., solution) may partially resolve this problem. 

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