Many cases of diarrhea resolve within a couple of days. Sometimes, however, it can persist for weeks.
Diarrhea is the medical term for passing loose, watery stools at least three times a day. Short-term and longer-term diarrhea may have different causes and may consequently require specific treatments.
This article provides information on how long diarrhea usually lasts and explores what causes this condition to persist for more than a week. We also outline home and medical treatments for diarrhea and offer advice on when to see a doctor.
Most cases of diarrhea last 1–2 days, though some may last longer. The exact duration depends on the underlying cause.
The National Institute of Diabetic and Digestive and Kidney Diseases (NIDDK) categorize the condition into three groups according to its duration:
- Acute diarrhea: Lasts for 1–2 days and goes away without medical treatment.
- Persistent diarrhea: Diarrhea that persists for 2–4 weeks.
- Chronic diarrhea: Continual or intermittent diarrhea lasting for more than 4 weeks.
Acute diarrhea often occurs due to a viral infection. These infections tend to clear up on their own within a few days.
When a person first experiences diarrhea, they may not know whether the condition will be acute, persistent, or chronic. People with diarrhea from an infection may experience additional symptoms, such as:
According to the NIDDK, persistent and chronic diarrhea may last more than a week. Both types may have different triggers.
Causes of persistent diarrhea
Below are the most common causes of persistent diarrhea.
Persistent diarrhea can occur as a result of viral, bacterial, or parasitic infections.
The table below shows the different types of pathogens that commonly cause diarrhea and how they may enter the body.
|Pathogen type||Example||How it can enter the body|
|Through inhaling infected droplets from another person’s coughs or sneezes|
By touching a surface that has come into contact with infected droplets, then touching the eyes, nose, or mouth
Escherichia Coli (E. Coli)
|Through contaminated food or water|
|Through contaminated food or water|
Travelers’ diarrhea (TD) is the medical term for diarrhea that results from consuming food or water contaminated with viruses, bacteria, or parasites.
Its name originates from the fact that it typically develops when people travel to countries with poor sanitation.
According to the NIDDK, TD typically causes acute diarrhea, though some parasitic infections may trigger persistent diarrhea.
Medication side effects
Certain medications can cause diarrhea as a side effect. Examples include:
Causes of chronic diarrhea
We explore potential triggers for chronic diarrhea below.
Without treatment, certain bacterial and parasitic infections may cause chronic diarrhea.
Following an infection, people may experience problems digesting certain carbohydrates and proteins. This can prolong the duration of diarrhea.
Food allergies and intolerances
Chronic diarrhea can sometimes indicate an underlying food allergy or intolerance. Food intolerance is when a person has difficulty digesting a particular food. This may lead to an upset stomach and diarrhea.
Some common types of food intolerance include:
- Lactose intolerance: Inability to properly digest lactose, a sugar found in milk and dairy products.
- Fructose intolerance: When the body cannot properly digest fructose, a sugar in fruits, fruit juices, and honey.
- Gluten intolerance: When a person cannot properly absorb gluten proteins, found in cereals.
In addition to the above, some people may have difficulty breaking down types of sugar alcohol in some sugar-free products. Examples include:
Chronic diarrhea can sometimes indicate an underlying issue within the digestive tract.
Some digestive conditions that may cause chronic diarrhea include:
- irritable bowel syndrome
- small intestinal bacterial overgrowth
- celiac disease
- inflammatory bowel diseases, such as ulcerative colitis and Crohn’s disease
A person may develop chronic diarrhea after surgery on the following organs:
- small or large intestine
Long-term antibiotic use
Long-term antibiotic use can also change the balance of good and bad gut bacteria. This can make a person more susceptible to infection with the diarrhea-causing bacteria Clostridium difficile.
Below are some remedies that may ease diarrhea and its associated symptoms.
There are two main types of anti-diarrheal medication available without a prescription:
- Loperamide: This drug is available under the brand name Imodium. It works by slowing down digestion so that the body can draw more water from the intestines. This helps firm up stools and reduces the frequency of bowel movements.
- Bismuth subsalicylate: This medication is available as Pepto Bismol. It works by coating and killing some of the gut bacteria that triggers diarrhea.
Changing the diet
People with diarrhea may find that eating bland and easily digestible foods could provide nutrition while settling the stomach and alleviating symptoms.
One such diet is the BRAT diet, which stands for bananas, rice, applesauce, and toast. Other foods that a person can eat while experiencing stomach upset include:
- steamed or boiled vegetables
- scrambled eggs
- chicken or turkey without the skin
- white bread
- white rice
- saltine crackers
People should also avoid foods that could worsen gastric upset and diarrhea, such as:
- fried, fatty, or spicy foods
- milk and dairy products, except for plain yogurt and kefir
- red meats
- raw vegetables
- citrus fruits
- extremely hot or cold drinks
Drinking plenty of fluids
Diarrhea can cause a person to lose fluids and essential electrolytes, which can lead to dehydration.
Drinking plenty of fluids will help reduce this risk. These fluids include:
- plain water
- low-sugar fruit juices
- low-sugar sports drinks
- clear broths
Treatments for persistent or chronic diarrhea depend on the underlying cause. Some possible causes and their treatment options are below.
A doctor may prescribe a course of antibiotics to treat a lingering bacterial infection, or an antiparasitic medication to manage a parasitic infection.
Food allergies and intolerances
If a person suspects they have a food allergy or intolerance, their doctor may recommend keeping a food diary.
People can use their diary to record the foods they eat on a day-to-day basis, and the symptoms they experience. Over time, this will help them detect foods that may trigger their diarrhea.
Treatment for a food allergy or intolerance typically involves avoiding known trigger foods.
The treatment for a digestive issue depends on the type of condition. Depending on the cause, it may involve one or more of the following:
- avoiding certain foods
- taking medications to control the underlying condition
- taking medicines to alleviate diarrhea and other gastrointestinal symptoms
- surgery to help treat the underlying condition
The NIDDK recommend that people see a doctor if their diarrhea lasts more than 2 days, or if they pass six or more loose stools in 24 hours.
A person should also seek medical attention for the following symptoms:
- frequent vomiting
- stools that are black, tarry, or contain blood
- severe pain in the abdomen or rectum
- signs of dehydration
Diarrhea that lasts for more than a week may be persistent or chronic.
Persistent diarrhea lasts for up to 4 weeks. This condition is typically the result of an infection or a side effect of medication.
Chronic diarrhea refers to diarrhea that lasts for 4 weeks or more. There are many potential triggers for this issue, including untreated infections, food allergies and intolerances, and underlying digestive conditions.
Anyone who experiences diarrhea that persists for more than 2 days should visit their doctor for a diagnosis and appropriate medical treatment.