Sections View Full Chapter Figures Tables Videos Full Chapter Figures Tables Videos Supplementary Content +++ INTRODUCTION ++ Constipation has been defined as difficult or infrequent passage of stool, at times associated with straining or a feeling of incomplete defecation. +++ PATHOPHYSIOLOGY ++ Constipation may be primary (occurs without an underlying identifiable cause) or secondary (the result of constipating drugs, lifestyle factors, or medical disorders). Constipation commonly results from a diet low in fiber, inadequate fluid intake, decreased physical activity, or from use of constipating drugs such as opiates. Constipation may sometimes be psychogenic in origin. Diseases or conditions that may cause constipation include the following: ✓ Gastrointestinal (GI) disorders: Irritable bowel syndrome (IBS), diverticulitis, upper and lower GI tract diseases, hemorrhoids, anal fissures, ulcerative proctitis, tumors, hernia, volvulus of the bowel, syphilis, tuberculosis, lymphogranuloma venereum, and Hirschsprung disease ✓ Metabolic and endocrine disorders: Diabetes mellitus with neuropathy, hypothyroidism, panhypopituitarism, pheochromocytoma, hypercalcemia, and enteric glucagon excess ✓ Pregnancy ✓ Cardiac disorders (eg, heart failure) ✓ Neurogenic constipation: Head trauma, CNS tumors, spinal cord injury, cerebrospinal accidents, and Parkinson disease ✓ Psychogenic causes Causes of drug-induced constipation are listed in Table 22–1. All opiate derivatives are associated with constipation, but the degree of intestinal inhibitory effects seems to differ among agents. Orally administered opiates appear to have greater inhibitory effect than parenterally administered agents; oral codeine is well known as a potent antimotility agent. ++Table Graphic Jump LocationTABLE 22–1Drugs Causing ConstipationView Table|Favorite Table|Download (.pdf) TABLE 22–1 Drugs Causing Constipation Analgesics Inhibitors of prostaglandin synthesis Opiates Anticholinergics Antihistamines Antiparkinsonian agents (eg, benztropine or trihexyphenidyl) Phenothiazines Tricyclic antidepressants Antacids containing calcium carbonate or aluminum hydroxide Barium sulfate Calcium channel antagonists Clonidine Diuretics (non–potassium-sparing) Ganglionic blockers Iron preparations Muscle blockers (d-tubocurarine, succinylcholine) Nonsteroidal anti-inflammatory agents Polystyrene sodium sulfonate +++ CLINICAL PRESENTATION ++ Table 22–2 shows the general clinical presentation of constipation. The patient should also be carefully questioned about usual diet and laxative regimens. General health status, signs of underlying medical illness (ie, hypothyroidism), and psychological status (eg, depression or other psychological illness) should also be assessed. Patients with alarm symptoms, a family history of colon cancer, or those older than 50 years with new symptoms may need further diagnostic evaluation. ++Table Graphic Jump LocationTABLE 22–2Clinical Presentation of ConstipationView Table|Favorite Table|Download (.pdf) TABLE 22–2 Clinical Presentation of Constipation Signs and symptoms Infrequent bowel movements (<3 per week) Stools that are hard, small, or dry Difficulty or pain of defecation Feeling of abdominal discomfort or bloating, incomplete evacuation, etc. Alarm signs and symptoms Hematochezia Melena Family history of colon cancer Family history of inflammatory bowel disease Anemia Weight loss Anorexia Nausea and vomiting Severe, persistent constipation that is refractory to treatment New-onset or worsening constipation in elderly without evidence of primary cause Physical examination Perform rectal exam for presence of anatomical abnormalities (such as fistulas, fissures, hemorrhoids, rectal prolapse) or abnormalities ... GET ACCESS TO THIS RESOURCE Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth Get Free Access Through Your Institution Contact your institution's library to ask if they subscribe to McGraw-Hill Medical Products. Access My Subscription GET ACCESS TO THIS RESOURCE Subscription Options Pay Per View Timed Access to all of AccessPharmacy 24 Hour $34.95 (USD) Buy Now 48 Hour $54.95 (USD) Buy Now Best Value AccessPharmacy Full Site: One-Year Individual Subscription $595 USD Buy Now View All Subscription Options