Diarrhea is characterized by unformed, watery stools (200 to 250 g/day) and increased bowel movement frequency, often accompanied by fever, chills, malaise. The symptom of an underlying condition or conditions, diarrhea is considered to be acute at onset, and chronic after two to three weeks. Although diarrhea is a common condition and usually self-limiting (two to three days), complications can be serious, even fatal, in infants and elderly patients, consequently it is important to attempt to determine the cause(s).

Diarrhea has four primary classifications.

• Osmotic: reduced solute absorption
• Secretory: increased electrolyte and water secretion
• Exudative: loss of fluid and protein from intestinal mucosa
• Motility disorder: intestinal transit alterations

Common causes include viral, bacterial, and parasitic infection (often spread person-to-person), inflammation, drugs, and psychogenic causes. In particular:

Acute:

• Infection (primary)
• Inflammatory bowel disease (primary)
• Iatrogenic causes
• Poisoning

Chronic:

• Malabsorption (notably lactose intolerance)
• Inflammatory bowel disease
• Colitis
• Irritable bowel syndrome
• Food allergies
• Giardia
• Chronic constipation
• AIDS and other immune disorders

Chronic subdivisions (multiple types of diarrhea may be present):

Osmotic diarrhea:

• Malabsorption
• Low sugar absorption (lactose intolerance)
• Antacids

Secretory diarrhea:

• Bacterial infections (e.g., cholera)
• Collagenous colitis
• Crohn's disease
• Celiac sprue
• Laxative abuse (common with chronic diarrhea)
• Tumors
• Hyperthyroidism

Exudative diarrhea:

• Bacterial infections (e.g., Shigella, Salmonella)
• Ulcerative colitis
• Inflammatory bowel disease

Motility disorder diarrhea:

• Irritable bowel syndrome
• Scleroderma
• Diabetes
• Surgical procedures
• Laxatives
• Hyperthyroidism

• Dairy products, some fruits and legumes
• Sugar substitutes (hexitols, sorbitol, mannitol)
• Hospitalization/surgery (iatrogenic)
• Foreign travel
• Hiking, camping, fishing trips
• Exposure to infected persons
• Medications (e.g., antibiotics, antacids, diuretics, antihypertensives, anti-inflammatories, and cardiovascular medications)
• Stress
• Recent antibiotic therapy

• Loose stools, with or without blood and mucus
• Frequent need to defecate
• Abdominal pain, cramping
• Fever, chills, malaise
• Weight loss

• Crohn's disease
• Colitis, ulcerative colitis
• Whipple's disease
• Inflammatory bowel disease
• Irritable bowel syndrome
• Reiter's syndrome
• Zollinger-Ellison syndrome
• Over-the-counter medications
• Various rare intestinal tumors (ganglioneuroblastoma, mucinous cystadenoma, and intestinal lipoblastoma)
• Congenital microvillous atrophy
• Congenital chloride diarrhea
• Magnesium or vitamin C supplementation

For most patients, diarrhea is relatively benign and self-limiting. A few patients, however, have an underlying illness that should be diagnosed and treated—in particular, patients with diarrhea that has persisted for longer than three days or with blood in the feces (suggesting exudative diarrhea). Determining the mechanism (osmotic, secretory, exudative, or motility) helps direct treatment.

Because patients will not be capable of reporting stool weight/day, patient history plays a major role in diagnosing diarrhea.

• Confirm that the condition is diarrhea, not fecal incontinence.
• Determine the volume type of diarrhea.
• Determine if diarrhea is acute (generally related to infection) or chronic.
• Note signs and symptoms.
• Ask patient about risk factors, lactose intolerance, antibiotics use, sexual orientation, and surgery.
• Explore the effect of diet. (Osmotic diarrhea generally ends when fasting. Secretory diarrhea generally does not end when fasting. Lactase deficiency generally is an accurate diagnosis if symptoms improve with the elimination of milk and dairy products).

Assess:

• Hydration
• Abdominal tenderness
• Bowel sounds
• Rectum (carcinoma, fecal impactions)

• Stool sample
• CBC
• Serum electrolytes
• BUN
• d-xylose
• Pancreatic function
• Urinalysis

Blood:

• Leukocytosis
• Pathogens
• Anemia
• Biochemical deficiencies

Endoscopy:

• Mucosal abnormalities
• Bleeding
• Ulcers

Stool:

• Blood (generally exudative diarrhea)
• Weight/volume
• Fecal fat
• Electrolytes
• Osmolality
• Parasites

• Small-bowel radiography
• Barium enema

In addition to patient history and physical assessment, endoscopy, laboratory tests (including stool analysis), and rectal biopsy (occasionally) can help determine the cause—and thus the treatment—of diarrhea.

Because diarrhea is a symptom, treatment should be dictated by the cause (or causes). For acute, uncomplicated diarrhea, it may be sufficient to reassure patients that the diarrhea is benign and will resolve in a couple of days and simply treat the symptoms.

For some chronic diarrhea, dietary change can be sufficient without additional evaluation.

Serious acute bloody diarrhea and chronic diarrhea will require evaluation and treatment of underlying cause(s). Hospitalization should be considered with dehydration; in any case, replacement of fluids (clear fluids without caffeine and rehydration fluids) and electrolytes—particularly with very young and very old patients—is critical.

Because some medications prescribed for diarrhea can delay resolution of certain infectious diarrhea conditions (as well as other contraindications), diarrhea should be diagnosed before drug therapy is undertaken. Common drug therapies (many OTC) include the following.

• Opioid derivatives: diphenoxylate-atropine (Lomotil) and loperamide (Imodium). May have CNS effect.
• Adsorbents: bismuth salts (Pepto-Bismol), kolin, and pectin (Kaopectate), aluminum hydroxide (Amphojel), cholestyramine (Questran)
• Bulk-forming medications: psyllium (Metamucil, Konsyl)

Specific guidelines include:

• Bismuth salts for traveler's diarrhea
• Cholestyramine for bile-acid-induced diarrhea

Severe diarrhea can be life-threatening, and it is imperative that the underlying etiology be assessed before initiating any treatment other than fluid replacement. Nutrition suggestions should be followed for all types of diarrhea.

• Avoid coffee, chocolate, dairy products, strong spices, and solid foods. Introduce clear soup, crackers and white bread, rice, potatoes, applesauce, and bananas as diarrhea begins to resolve. Sips of black tea may help settle the stomach when nausea is present.
• To restore and maintain fluid and electrolyte balance, consider rice and/or barley water, fresh vegetable juices (especially carrot and celery), miso broth, or other clear broths. Rice and barley water are made using 1 cup of grain to 1 quart of boiling water. Let steep for 20 minutes. Strain and drink throughout the day.
• Lactobacillus species taken as powder or in capsules helps to normalize bowel flora and may help resolve diarrhea. Take as directed, or one dose with each meal. Saccharomyces bolardii and brewer's yeast are specific for treating antibiotic-induced diarrhea that has caused Clostridium difficile overgrowth.
• Vitamin C (1,000 mg tid to qid) and vitamin A (10,000 to 20,000 IU/day) support immune function. High doses of vitamin C may cause diarrhea. High doses of vitamin A should not be taken long-term without physician supervision.
• Glutamine (3,000 mg tid) is helpful to treat diarrhea that is caused by mucosal irritation rather than infection, such as chemotherapy-induced diarrhea.

Herbs are generally a safe way to strengthen and tone the body's systems. As with any therapy, it is important to ascertain a diagnosis before pursuing treatment. Herbs may be used as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, teas should be made with 1 tsp. herb per cup of hot water. Steep covered 5 to 10 minutes for leaf or flowers, and 10 to 20 minutes for roots. Drink 2 to 4 cups/day. Tinctures may be used singly or in combination as noted.

Do not initiate antidiarrheal therapy if the diarrhea is secondary to an infectious agent. Herbs can be used as anti-inflammatories, antimicrobials, or antidiarrheals. Choose one or two from each category as needed. They are best used as teas unless otherwise noted.

Anti-inflammatory herbs:

• Quercetin (250 to 500 mg bid to qid)
• Chamomile (Matricaria recutita) is a soothing antispasmodic.
• Marshmallow root (Althea officinalis) is best prepared as cold-water tea. Soak 2 tbsp. root in one quart of water overnight. Strain and drink throughout the day.

Antimicrobial herbs:

• Barberry (Berberis vulgaris), 250 to 500 mg tid
• Goldenseal (Hydrastis canadensis), 250 to 500 mg tid
• Licorice root (Glycyrrhiza glabra) (contraindicated in hypertension)

Antidiarrheal herbs:

• Blackberry leaf (Rubus fruticosus) or raspberry leaf (Rubus idaeus)—use 1 heaping tsp./cup. Drink 1/2 cup per hour.
• Carob powder—use 4 tsp. per 4 oz. of water or mix in applesauce. Take 1/2 to 1 tsp. every 30 to 60 minutes.
• Slippery elm powder (Ulmus fulva) or marshmallow root powder—use 1 oz. powder to 1 quart of water. Make a paste with the powder and a small amount of water. Gradually add in the rest of the water and then simmer down to one pint. Take 1 tsp. every 30 to 60 minutes.

An experienced homeopath should assess individual constitutional types and severity of disease to select the correct remedy and potency. For acute prescribing use 3 to 5 pellets of a 12X to 30C remedy every one to four hours until acute symptoms resolve.

• Arsenicum album when patient is weak, chilly, anxious, and restless with diarrhea.
• Podophyllum for yellow, explosive, gushing, gurgling, painless diarrhea
• Chamomilla for greenish, frothy stool with severe colicky pains; stool smells like rotten eggs.
• Mercurius vivus for strong urging with offensive, bloody diarrhea.
• Aloe for colicky, cramping pains before and during stool. Weak and sweaty after diarrhea.
• Veratrum album for diarrhea and vomiting, collapsed states.

Dehydrated patients and infant and elderly patients with serious signs and symptoms should be monitored carefully. Patients with acute diarrhea should report conditions that do not resolve in three to five days. Follow up with chronic patients as required.

Avoid risk factors as possible.

• Dehydration
• Syncope, arrhythmias (from loss of electrolytes)
• Anemia

• Acute: generally resolves in two to three days
• Chronic, idiopathic diarrhea: generally self-limiting, although it may continue indefinitely

Dehydration can cause preterm labor. Gastrointestinal spasm may have reflexive action on uterine muscle and induce contractions. Goldenseal (Hydrastis canadensis) and barberry (Berberis vulgaris) should be avoided in pregnancy as they may stimulate contractions. High doses of vitamin A may be teratogenic and should be avoided.

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