DISORDERS OF THE GASTROINTESTINAL TRACT
DIARRHEA
General Therapy for Diarrhea
Diet. If nausea and vomiting do not prevent eating, adjust the diet:
Dehydration can be estimated as follows:
In a baby, dehydration is manifest as dry diaper (decreased urine output), sunken eyes, sunken “soft spot” (fontanel) on the top of the head, dry tongue and mouth, rapid pulse, poor skin color (blue or pale), lethargy (“floppy baby”), and fast breathing (greater than 30 breaths per minute in a small child, or 40 per minute in an infant). For purposes of estimation, a normal pulse rate (per minute) in a newborn averages 120; at 2 years, 110; at 4 to 6 years, 100; and at 8 to 10 years, 90.
Fluid replacement. If fluid losses are significant (more than five bowel movements per day), begin to replace liquids as soon as you can.
Antimotility (decreased bowel activity) drugs. If fever, severe cramping, and bloody diarrhea are absent, it is safe to use antimotility drugs, although they should be immediately discontinued if diarrhea lasts for more than 48 hours. If diarrhea lasts longer than 3 days, if the victim has a fever greater than 101°F (38.3°C), if he cannot keep liquids down because of vomiting, if there is blood in or on the stool, if the abdomen becomes swollen, or if there is no significant pain relief after 24 hours, seek a physician immediately.
The antimotility drug of choice is loperamide (Imodium A-D). The initial adult dose is 4 mg (two 2 mg capsules, or 4 tsp—20 mL—of the liquid), followed by 2 mg after each loose bowel movement, not to exceed 16 mg (eight capsules) per day or 2 days of administration. With uncomplicated (no fever or blood in stools), watery diarrhea, this drug can be given to children age 2 years and older. Give children a 0.2 mg/kg (2.2 lb) of body weight dose every 6 hours. The liquid preparation contains 1 mg/tsp (5 mL).
For adults, diphenoxylate (Lomotil) is an alternative, but has side effects of dry mouth and urinary retention. Pepto-Bismol is another, less effective choice (see page 212).
Kaopectate (kaolin plus pectin) is of limited value; it does not shorten the course of diarrheal illness, and acts only to add a little consistency to stools. Lactobacillus preparations (acidophilus beverages or yogurt) do not shorten the course of acute diarrheal illness, but they may be useful to repopulate the gastrointestinal tract with normal bacteria after a severe bout of diarrhea or administration of antibiotics used to treat diarrhea.
In foreign countries, drugs are on occasion recommended for diarrhea without a specific diagnosis. These drugs include chloramphenicol (Chloromycetin), Enterovioform, MexaForm, Intestopan, clioquinol, and iodoquinol. This may be dangerous, because these drugs can have certain adverse direct effects or side effects. Therefore, they should not be taken without a specific diagnosis for which they are felt to be indicated.
Antibiotics. These should be used if diarrhea is moderate to severe (more than eight bowel movements per day), particularly if it is bloody and associated with severe cramping, vomiting, and fever.
Traveler’s Diarrhea
Traveler’s diarrhea (“turista,” “Kathmandu quickstep,” “Montezuma’s revenge,” “Delhi belly,” “Aztec two-step,” “Hong Kong dog,” and many other synonyms) is frequent, loose bowel movements (three or more loose stools in a 24-hour period associated with one or more of nausea, vomiting, abdominal cramps, fever, urge to defecate, cramping and straining with defecation, or bloody or mucus-laden stools) caused by waterborne or food-borne pathogens, most commonly produced by forms of the bacterium Escherichia coli, which is introduced into the diet as a fecal contaminant in water or on food. Someone has described it as “stool that fits the shape of the container.” When caused by E. coli, symptoms usually occur 12 to 36 hours after ingesting the bacteria, and include the gradual or sudden onset of frequent (four to five per day) loose or watery bowel movements, rarely explosive, and far less violent than diarrhea associated with classic food poisoning (see below). Fever, bloating, fatigue, and abdominal pain are of minor to moderate severity. Nausea and vomiting are less frequently found than with viral gastroenteritis. Most traveler’s diarrhea is caused by bacteria, but a small percentage may be caused by viruses or parasites.