Diarrhea describes loose, watery stools that occur more frequently than usual. Diarrhea is something everyone experiences. Diarrhea often means more-frequent trips to the toilet and a greater volume of stool.
In most cases, diarrhea signs and symptoms usually last a couple of days. But sometimes diarrhea can last for weeks. In these situations, diarrhea can be a sign of a serious disorder, such as inflammatory bowel disease, or a less serious condition, such as irritable bowel syndrome.
Bacterial Causes of Diarrhea
Bacteria are part of everyday life, and normally bacteria and humans live together peacefully. However, some bacteria can wreak havoc on your digestive well-being. These tiny bugs find fertile breeding ground in raw meats, eggs, shellfish, and unpasteurized milk.
Viral Causes of Diarrhea
Some viral infections can lead to diarrhea and vomiting. These viral strains are highly contagious, traveling easily from unwashed hand to unwashed hand. Shared drinks, utensils, and contaminated food also provide passage into your unsuspecting stomach. People who no longer have symptoms or never exhibited symptoms in the first place can sometimes spread these viruses.
Diarrhea is the reversal of the normal net absorptive status of water and electrolyte absorption to secretion. Such a derangement can be the result of either an osmotic force that acts in the lumen to drive water into the gut or the result of an active secre¬tory state induced in the enterocytes. In the former case, diarrhea is osmolar in nature, as is observed after the ingestion of nonabsorbable sugars such as lactulose or lactose in lactose malabsorbers. Instead, in the typical active secretory state, enhanced anion secretion (mostly by the crypt cell compartment) is best exemplified by enterotoxin-¬induced diarrhea.
In osmotic diarrhea, stool output is proportional to the intake of the unabsorbable substrate and is usually not massive; diarrheal stools promptly regress with discontinuation of the offending nutrient, and the stool ion gap is high, exceeding 100 mOsm/kg. In fact, the fecal osmolality in this circumstance is accounted for not only by the electrolytes but also by the unabsorbed nutrient(s) and their degradation products. The ion gap is obtained by subtracting the concentration of the elec¬trolytes from total osmolality (assumed to be 290 mOsm/kg), according to the formula: ion gap = 290 – [(Na + K) × 2].
In secretory diarrhea, the epithelial cells’ ion transport processes are turned into a state of active secretion. The most common cause of acute-onset secretory diarrhea is a bacterial infection of the gut. Several mechanisms may be at work. After colonization, enteric pathogens may adhere to or invade the epithelium; they may produce enterotoxins (exotoxins that elicit secretion by increasing an intracellular second messenger) or cytotoxins. They may also trigger release of cytokines attracting inflammatory cells, which, in turn, contribute to the acti¬vated secretion by inducing the release of agents such as prostaglandins or platelet-activating factor. Features of secretory diarrhea include a high purg¬ing rate, a lack of response to fasting, and a normal stool ion gap (ie, 100 mOsm/kg or less), indicating that nutrient absorption is intact.
Run-of-the-Mill Diarrhea Symptoms
Diarrhea makes its presence known with the urgency, frequency, and volume of your trips to the bathroom. You know that it’s diarrhea when you pass loose, watery stool two to three times a day or more. These other symptoms can also accompany diarrhea:
- Abdominal pain
A doctor will complete a physical examination and consider your medical history when determining the cause of your diarrhea. They may also request laboratory tests to examine urine and blood samples. Additional tests your doctor may order to determine the cause of diarrhea and other related conditions can include:
- fasting tests to determine whether a food intolerance or allergy is to blame
- imaging tests to check for inflammation and structural abnormalities of the intestine
- stool culture to check for bacteria, parasites, or signs of disease
- colonoscopy to check the entire colon for signs of intestinal disease
- sigmoidoscopy to check the rectum and lower colon for signs of intestinal disease
In cases of severe or chronic diarrhea, your doctor may order a colonoscopy or sigmoidoscopy to determine if an underlying intestinal condition is the cause.
Most cases of diarrhea clear on their own within a couple of days without treatment. If you’ve tried lifestyle changes and home remedies for diarrhea without success, your doctor may recommend medications or other treatments.
Antibiotics may help treat diarrhea caused by bacteria or parasites. If a virus is causing your diarrhea, antibiotics won’t help.
Treatment to replace fluids
Your doctor likely will advise you to take steps to replace the fluids and salts lost during diarrhea. For most people, replacing fluids means drinking water, juice or broth. If drinking liquids upsets your stomach or causes diarrhea, your doctor may recommend getting fluids through a vein in your arm (intravenously).
Water is a good way to replace fluids, but it doesn’t contain the salts and electrolytes — minerals such as sodium and potassium — you need in order to maintain the electric currents that keep your heart beating. Disruption of your body’s fluid and mineral levels creates an electrolyte imbalance that can be serious. You can help maintain your electrolyte levels by drinking fruit juices for potassium or eating soups for sodium.