Diarrhea
Diarrhea is usually defined as multiple loose or watery bowel
movements, many times more frequent than one’s usual pattern.
Some people describe diarrhea, but are only having one loose
stool per day. This is a change in their bowel habit, but
not really diarrhea.
There are many causes for diarrhea, but on this page I will
review some of the more common causes for both acute (sudden
onset) and chronic (long lasting) diarrhea.
1. Acute Diarrhea
a. Infections – the most common causes are food poisoning
due to ingested toxins, bacteria, viruses and parasites (like giardia, amebas, cyclospora). These usually resolve on
their own within 1-7 days. Treatment is most helpful with
some of the bacteria and parasites. (Parasitic symptoms may last
for weeks or months.)
b. Gastrointestinal Disorders – such as partial bowel
obstruction (with prior surgeries), fecal impaction (especially
in nursing home patients) ischemic colitis (in middle aged
women), diverticulitis and the initial attacks of ulcerative
colitis and crohn’s disease.
c. Drugs – side effects of many drugs can include
diarrhea. Some examples include: anti-hypertensives,
antibiotics, iron, some anti-depressants, diabetic and arthritis
medications. Some patients are inadvertently taking
laxatives or sugar-free foods with sorbitol that cause diarrhea.
d. Antibiotic Colitis – doesn’t occur when taking the
antibiotics, but usually begins within 1-4 weeks after finishing
a course of antibiotic treatment. The diarrhea may be
severe, and requires medical treatment most of the time.
e. Unusual Causes – like hyperthyroidism or carcinoid
syndrome.
2. Chronic Diarrhea
This is when the loose bowel movement persists for more than 3
weeks. The possible reasons are listed below:
a. Inflammatory bowel diseases – things such as ulcerative
colitis, crohn’s disease, microscopic colitis (lymphocytic and
collagenous colitis).
b. After Bowel Resection or Radiation – after gastrectomy,
cholecystectomy (gallbladder removal), vagotomy, or radiation
treatment that effects the bowel
c. After or during chemotherapy.
d. With the irritable bowel syndrome (IBS).
e. Celiac Sprue
f. Unusual causes – certain cancers, unusual tumors,
thyroid dysfunction, malabsorption, scleroderma, diabetes and
pancreatic problems.
Diarrhea can be treated in most cases. Finding the cause, however, is the key. Having bloody diarrhea, abdominal pain or fever with loose stools is most alarming, and requires prompt medical attention. Lab tests of the stool and blood, as well as Colonoscopy may be warranted. These can only be considered after a thorough history and physical exam.
