Diarrhea is a very unpleasant symptom that almost everyone has experienced. Generally, strict hygiene is very important with diarrheal diseases to prevent transmission to other people. While many people associate diarrhea with food poisoning or gastrointestinal infection, other conditions such as hormonal imbalances or irritable bowel syndrome (IBS) may cause diarrhea. In rare cases, a malignant disease might even be hiding behind diarrhea, so a medical examination is required for severe or prolonged symptoms.
What exactly is diarrhea?
Diarrhea is considered present when:
- A person needs to go to the bathroom more than three times per day,
- The stool is of watery or low viscosity/mushy consistency (Bristol Stool Scale 5 or higher), and
- The amount of stool is more than 250 grams per day.
In reality, the frequency and texture (consistency) of the stool varies for each individual, so it can sometimes be difficult to decide if the criteria apply. For example, the amount of stool may well exceed 250 grams with a high-fiber diet. It may also be that a healthy person has solid bowel movements more than three times daily, which would not be considered diarrhea. Thus, it is important to take into account changes in frequency and consistency.
Diarrhea is also divided according to how long it lasts:
- Acute diarrhea lasts for a maximum of two to four weeks
- Chronic diarrhea is referred to as having a duration of at least four weeks
How is diarrhea treated?
Most cases of acute diarrhea are treated symptomatically (the symptoms rather than the cause are treated). In most cases, acute diarrhea will cease after 3-5 days without causative treatment.
With strong diarrhea, the body loses a lot of water and electrolytes, so it is important to replace these. Fruit juices and sodas such as cola are not suitable for this because the high sugar content can increase diarrhea.
For very severe diarrhea such as with cholera, the so-called WHO drinking solution is used, which is also known as the ORS (Oral Rehydration Solution). One liter of this solution for diarrhea consists of the following:
- 13.5 grams of glucose
- 2.9 grams of sodium citrate
- 2.6 grams of common salt (sodium chloride)
- 1.5 grams of potassium chloride
The WHO solution is used for severe salt and water loss from diarrhea. It is available over the counter in the drugstore. 40 milliliters of the solution per kilogram of body weight should be consumed every 24 hours, which is about 3 liters at a body weight of 165 pounds (75 kilograms).
Which other home remedies help against diarrhea?
In general, it is important to compensate for the loss of fluid and electrolytes. One should drink plenty of water or tea, and administer electrolytes. There are special ready-mixed, over-the-counter drugs in the drugstore for this purpose.
In addition, there are some herbal home remedies that could possibly help with diarrhea. These include grated apple, psyllium seed (husks), dried blueberries, blackberry leaves, carrot soup, and tormentil and uzara root. Although some laboratory studies and animal studies indicate that these home remedies may help with diarrhea, no clinical studies have adequately studied the effect of their ingredients on humans. Therefore, the use of these home remedies cannot be recommended by physicians.
Do herbal home remedies for diarrhea work?
The possible effect of grated raw apple against diarrhea is based on there being so-called pectins (plant polysaccharides) directly below apple skin. Pectins act as swelling agents in the intestine and can bind fluid and toxins. The key is that the apple needs to be grated with skin, as it contains a large proportion of pectins. Otherwise, the effects described in experiential reports could fail.
The use of psyllium is based on a similar principle. According to experiential reports, shredded psyllium husks work best. These are mixed in a little water and then drunk. Psyllium seeds are versatile and probably useful not only against diarrhea but also against constipation. They may contribute to healthy stool consistency.
Blueberries and blackberry leaves
Blueberries and blackberry leaves have been regarded as effective home remedies for diarrhea for centuries, although there are no studies that can substantiate this fact. Experts in alternative medicine say that one should use dried rather than fresh fruit when using blueberries for diarrhea.
A high concentration of tannins is contained in dried blueberries, which is probably effective for diarrhea. Tannins may protect the mucous membranes from the pathogens and prevent excessive water excretion.
Blackberry leaves can be drunk in the form of an infusion as a tea. They also contain tannins and probably have the same effect as the dried blueberries.
However, many gastrointestinal physicians complain that no controlled studies on the efficacy of tannins in diarrhea and their use have been conducted, and therefore this treatment cannot be recommended.
“Moro’s” carrot soup also provides another effective mechanism. Ernst Moro was a pediatrician and discovered the effect of carrot soup against diarrhea in the early 20th century. The ingredients of this soup are very simple: Carrots, water, and some salt.
The key, according to alternative medicine, is that the carrots are cooked for a long time and then pureed. This results in sugar molecules, so-called oligogalacturonides. Pathogenic germs normally bind to structures of the intestinal wall. Oligogalacturonides probably mimic these structures of the intestinal wall. As a result, the pathogens that bind to these sugar molecules are excreted with these molecules.
The harmful effect of the germs on the intestinal wall and thus the diarrhea are alleviated. Whether this theoretically plausible concept actually improves the symptoms of diarrhea in practice has not been tested in clinical trials.
Tormentil root may also be effective against diarrhea, with a tannin content of up to 22 percent and other ingredients such as triterpenes. Tormentil is taken in the form of tea, which is obtained from an infusion of about 0.07 ounces (2 grams) of dried tormentil root. Due to its ingredients, tormentil root is said to have anti-inflammatory, wound-healing, and mucous membrane-protecting properties and helps to counteract the loss of water.
In a small study of children with rotavirus (a diarrhea-causing disease), it was shown that in children who received extract from tormentil root, diarrhea ceased after three days.
Similarly, uzara root, from South Africa, may have an antispasmodic effect and possibly inhibit the loss of water and electrolytes in the intestine. However, both tormentil and uzara root have so far been insufficiently studied, so doctors cannot recommend their use.
In the past, extracts from the opium poppy were also used, as it contains morphine-like substances (opioids), which have an analgesic and anti-intestinal effect. However, this has become an uncommon treatment due to the addictive potential.
What diarrhea medications help?
There are some medications that can be used with acute diarrhea:
Inhibition of bowel movements/reduction of stool frequency and quantity:
- Loperamide (but not for all diarrheal causes)
Relief of pain and abdominal cramps:
- Good: paracetamol (acetaminophen), metamizole, opioids, butylscopolamine
- Should be avoided: aspirin, ibuprofen, and other cortisone-free analgesics (NSAIDs)
Loperamide in particular helps to alleviate diarrhea and thus prevent significant loss of water. Loperamide can also be used as a drug with IBS and with chronic diarrhea. In the case of diarrhea caused by an illness, however, the use of loperamide may delay the course of the disease, as the excretion of the pathogen is slowed down. Therefore, the use of loperamide should be weighed, and a doctor should be consulted.
Antibiotics are used for travelers' diarrhea, typhus, cholera, and clostridium difficile infections. For parasitic diseases such as giardiasis and amoebiasis (entamoeba histolytica), special antiparasitic agents are used.
Can probiotics help with diarrhea?
Probiotics such as lactic acid bacteria can shorten the duration of acute diarrhea by about one day. The probiotic bacteria settle in the intestine and displace the harmful bacteria.
A systematic analysis of the Cochrane Collaboration of all relevant studies (meta-analysis) has shown that the intake of probiotics reduces the duration of diarrhea symptoms on average by about 24 hours. Patients suffering from IBS may also benefit from probiotics.
Another review has shown that probiotics are also helpful in the prevention of antibiotic-associated diarrhea. Saccharomyces boulardii and Lactobacillus have proven to be the most effective bacteria, here.
Probiotics are offered in capsules or in powder form in drugstores. Also some yogurts from the supermarket contain lactic acid bacteria. However, it is not clear whether all these remedies work equally well or at all. This topic is currently being intensively researched.
Traveler's diarrhea: what helps when traveling?
Traveler's diarrhea is diarrhea that occurs in Mediterranean, subtropical, or tropical countries. It is generally caused by bacteria or viruses absorbed in contaminated drinking water or food. Common bacterial pathogens include enteropathogenic (enteric) escherichia coli (especially ETEC: enterotoxin-producing e. coli), campylobacter species, salmonella, shigella, aeromonas, and plesiomonas.
In rare cases, infection with parasites or worms may be the cause of the diarrhea. Traveler's diarrhea occurs 90 percent of the time within the first two weeks of traveling and lasts for an average of 3-5 days.
In addition, diarrhea sufferers also often suffer from vomiting, weakness, and fatigue. As with acute diarrhea, fluid and electrolyte replacement (e.g. with WHO solution) is the most important treatment. If diarrhea persists for more than three days, is slimy or bloody, and is accompanied by a strong fever, consult a doctor.
Antibiotics are often needed with fevers and bloody diarrhea, or in patients with weakened immune systems. Antibiotics such as ciprofloxacin (a fluoroquinolone), azithromycin, and rifaximin can be used here. Rifaximin has been on the market since 2008 and has the advantage of being effective only in the intestine, so it does not cause side effects throughout the body (systemically) as it is not absorbed by the intestinal mucosa.
For some time, postinfectious irritable bowel syndrome has increasingly come in focus as a complication of traveler's diarrhea. Affected individuals may experience symptoms ofIBS for months to years, developing diarrhea (but also periods of constipation) in conjunction with abdominal pain and flatulence.
What if diarrhea does not get better?
If the symptoms do not improve after one week, a doctor should be consulted, since there is a suspicion either that the pathogen is remaining in the body and the body's own defenses to combat the pathogen are insufficient or that another cause is behind the diarrhea.
What causes diarrhea?
There are many causes of diarrhea. The most common causes are infections of the gastrointestinal tract. Various bacteria, viruses, and parasites can lead to diarrhea. Depending on the pathogen, the type of diarrhea differs in terms of duration, and whether it is bloody or watery. Some of these pathogens must also be reported. You should consult a doctor either if the symptoms start soon after a long-distance journey, or if in addition to diarrhea, other strong signs are present, such as
- Joint pain, or
- Bloody/mucousy stool.
Anyone who relies on home remedies when these symptoms are present may endanger themselves and others nearby.
The most common cause of acute diarrhea in Western countries is an infection with noroviruses in adults. In children, the most common pathogen is the rotavirus. These viruses can spread quickly especially in facilities where many people come together. According to the Robert Koch Institute, in adults every second and in children every third non-bacterial diarrheal disease is caused by norovirus. An infection should also be excluded as a cause with chronic diarrhea. Other causes may need to be considered, as well.
In addition to noroviruses, other pathogens, such as the consumption of pathogenic bacteria, may be responsible for acute diarrhea. Bacterial toxins in the context of food poisoning can also lead to diarrhea.
A list of pathogens according to probability shows that known pathogens, such as salmonella, are responsible for only 14 percent of proven causative agents for diarrhea.
The most common diarrhea causes with typical sources include:
- Norovirus (feces, vomit)
- Campylobacter (poultry liver, meat, pets)
- Rotaviruses (feces, vomit)
- Salmonella (foods such as eggs, meat and sausages, feces from humans, and echinoderms)
- E. coli (feces, food, drinking water)
- Yersinien (meat, vegetables)
- Lamblia (water)
- Cryptosporids (animal feces)
- Shigella (feces)
- EHEC (feces, food, drinking water)
In food poisoning, bacteria (staphylococci) often plays a role in the development of diarrhea. The bacteria themselves are not responsible for the diarrhea, but the toxins, called enterotoxins, which are formed by bacteria in spoiled food are.
When traveling, e. coli bacteria are very often the cause of violent diarrhea.
Food intolerances such as lactose intolerance or fructose intolerance can also cause acute diarrhea. However, the symptoms often have different degrees and it depends on the amount of incompatible food consumed. Some also consider intolerances to be types of chronic diarrhea.
Do medicines cause acute diarrhea?
Although antibiotics are used to treat some diarrheal diseases, they can also be the cause of diarrhea, as some antibiotics attack the intestinal flora. If there is an increase in harmful bacteria (such as the bacterium clostridium difficile), pseudomembranous colitis can occur as a dangerous complication. This is primarily treated with antibiotics that are effective against the pathologically increased bacteria. In lengthy and recurrent cases, a stool transplantation can also be considered.
Many doctors recommend probiotic medication during or after taking antibiotics to prevent antibiotic-related diarrhea. An evaluation of clinical studies on this topic confirms the effectiveness of this measure.
How does diarrhea develop in the intestine?
To understand what helps against diarrhea, the causes of bowel problems should be considered.
The food we consume is broken down into its constituents in the small intestine, after gastric passage, to be ingested by the body. The food that cannot be ingested continues to migrate to the digestive tract. The stool is then deprived of water, primarily in the colon, so that the feces becomes firmer.
In the case of diarrhea, however, this process is disturbed for various reasons:
Sometimes the body even releases water from the body into the intestine. If nutritional components cannot be ingested (e.g. FODMAPs) or if other substances (such as medications) are present in the intestines, the imbalance of electrolytes causes water to be drawn into the intestine. This effect is actually used by laxatives which thereby have an effect on constipation.
The intestinal mucosa gives off electrolytes in this form of diarrhea, so water follows into the intestine. This occurs, for example, in the context of food poisoning.
This form of diarrhea occurs in inflammation of the intestinal mucosa. Blood and mucus are secreted. This may be the case with parasites, inflammatory bowel disease, or colon cancer.
If intestinal motility is increased, the stool in the intestine cannot stay there long enough, so not enough liquid can be absorbed. Hypermotile diarrhea (diarrhea due to excessive bowel movements) is therefore also a symptom of irritable bowel syndrome.
Steatorrhea (fatty stool)
Fatty stool is a special form of diarrhea. Mostly, the stool has a large volume, and affected people can see even small drops of fat floating on the water after a bowel movement. The cause is often a lack of digestive juices, which are important for splitting fats.
What causes chronic diarrhea?
If diarrhea occurs for more than a four-week period, it is deemed chronic diarrhea. While this is always very distressing for sufferers, the causes for it (from relatively harmless to serious illnesses) can be very different.
By collecting the patient history (anamnesis), many insights can be gained. For example, if the chronic symptoms have occurred in a relatively short period of time (< 3 months) as well as at night, and there is weight loss, a physical (organic) cause is likely. And with a very long history of the illness, the absence of nocturnal diarrhea, and a constant body weight, it is more likely to be associated with IBS. Here are some causes of chronic diarrhea:
Poor utilization of nutrients
The poor utilization of nutrients is also referred to as malassimilation. This is divided into maldigestion and malabsorption.
If the digestive enzymes responsible for food breakdown are absent or do not enter the intestine, nutrients cannot be absorbed. Doctors call this process maldigestion. The causes can be a poorly functioning pancreas (pancreatic insufficiency) or a loss of bile acids. But lactose intolerance is also an example of maldigestion.
When nutrients decompose but cannot be absorbed by the intestinal mucosa, it is called malabsorption. This occurs, for example, with gluten intolerance (celiac disease).
The stools in the context of a malassimilation are mostly voluminous, foul-smelling, and fatty.
Irritable bowel syndrome
Chronic diarrhea sometimes occurs without doctors finding a physical cause for it. In most cases, an irritable bowel diagnosis can be made; it is also called a “functional disease.” Irritable bowel symptoms often include diarrhea, pain, flatulence, or constipation.
Other causes of chronic diarrhea
Other causes of chronic diarrhea are the chronic inflammatory bowel diseases ulcerative colitis and Crohn's disease. Bloody, slimy diarrhea is prevalent in these diseases.
Parasites such as giardia lamblia, entamoeba histolytica, and cryptosporidium parvum can cause chronic diarrhea especially after a stay abroad. A hormonal imbalance can also lead to diarrhea. Hyperthyroidism, for example, can increase intestinal motility.
Which tests are necessary for diarrhea?
With acute diarrhea, the patient history (anamnesis) is important. In many cases, no further examinations are necessary if the symptoms and the overall situation do not indicate a critical event.
If, for example, it turns out that several people are suffering from acute diarrhea at the workplace of the person concerned and no other risk factors (such as bloody diarrhea) exist, treatment of the symptoms is usually sufficient.
In addition to the general physical examination, the following examinations may initially be carried out:
- Ultrasound of the abdomen
- Blood test
A microbiological stool test (an examination of the stool for pathogenic germs) is not always necessary and depends on symptoms and the patient history. However, chronic diarrhea associated with traveler's diarrhea should always be preceded by a microbiological stool examination.
- Hydrogen breath test with suspicion of lactose intolerance or bacterial overgrowth
- Small intestinal mirroring with sampling, for example, with suspected gluten intolerance
Genetic analysis of the bacterial flora (microbiome) is not yet being carried out for diagnostic purposes, but in the future this method will presumably become more important.
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