Laxative drugs

Oral 2 mg tablets, capsules 1 mg/5 mL liquid Selected Laxative Drugs ... 

Department of Health and Human Services. (1998) Laxative Drug Products for Over-the-Counter Human Use Proposed Amendment to the Tentative Final Monograph. Federal Register. 63, 33592-33595. 

Anonymous. Laxative drug products for over-the-counter human use proposed amendment to the tentative final monograph. 21 CFRParts 310 and 334. Fed Register 1998 63 33592-5. 

Adjuncts used in addition to contrast agents in diagnostic radiography, under patient group directions, include laxatives, drugs to relax the bowel, normal saline and topical anaesthesia. 

List three laxative drugs and describe their mechanisms. 

Table 60-1. The major laxative mechanisms and some representative laxative drugs.

The related sennosides, glycosides A, B, C and D, occur in amounts of 1.5-3% in the leaves of Egyptian senna shrubs that are cultivated primarily in India. Senna leaves were previously used by Arab physicians as a laxative drug and digestive stimulant. Heterobianthrones sennosides A (meso-derivative, 9-169) and B (trans-derivative, 9-170) are bianthrone glycosides derived from aloe-emodin and rhein, homobianthrones sennosides C meso-derivative) and D (tra s-derivative) are derived only from rhein. 

Laxatives—Drugs such eis atropine and diuretics may make some people constipated, so laxatives may sometimes be added to such mixed medications. Some misinformed people also use excessive amounts of laxatives to cause weight loss which results in an increeised loss of nutrients and water in the stool. 

B. Take a daily laxative because die drug will likely cause constipation. 

There are various types of laxatives (see the Summary Drug Table Dm Used in the Management of Gastrointestinal Disorders). The action of each laxative is somewhat different, yet they produce the same result—the relief of constipation (Display 48-1). 

Constipation may occur as an adverse drug reaction. When the patient has constipation as an adverse reaction to another drug, the primary care provider may prescribe a stool softener or another laxative to prevent constipation during the drug therapy. Display 48-2 lists the names of some dm and drug classifications that may cause constipation. 

Do not use the drug indiscriminately. Check with a primary health care provider before using an antacid if other medical problems, such as a cardiac condition (some laxatives contain sodium), exist. 

DOSS itself is used as a laxative and cermumenolytic drug [71]. It is included in over-the-counter hematinic vitamin and mineral preparations to counteract the constipating effect of the iron contained in these products. In combination with anthrachinones, widespread use as catharic and emollient laxative is indicated [71-75]. 

Acquired disease of muscle is more common than is generally appreciated. It may result from the use of drugs—prescription or nonprescription—that have a recognized capacity to compromise the structure or function of skeletal muscle. Drugs particularly well recognized as myotoxic include clofibrate and its derivatives, anabolic steroids, penicillamine, and emetine. Many nonprescription drugs, including alcohol and laxatives, are directly or indirectly myotoxic. Other forms of acquired myopathies include the acute myopathic conditions caused by the bites of many snakes. 

Some drugs act as Indicators (e.g. phenolphthaleln, vegetable laxatives) and affect tests carried out at a particular pH. The presence of sulfobromophthaleln dye (BSP) In serum will Interfere with serum protein determined by the biuret method. 

Oral laxatives are the primary pharmacologic intervention for relief of constipation (Table 18-2). There are several different drug classes, as described below. 

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. 

Methylnaltrexone was launched in 2008 for the treatment of OIC in patients with advanced illness receiving palliative care, when response to laxative therapy has not been sufficient. Due to its poor oral bioavailability, 4 is administered subcutaneously every other day. Approximately 50% of the drug is excreted in the urine and feces with 85% eliminated unchanged [30]. 

---