Why Do You Have Diarrhea? Causes & How to Stop It

Key takeaways:

• Diarrhea is often a temporary issue caused by infections, changes in diet, or stress, but it can sometimes indicate a more serious health condition.
• Mild cases are usually manageable at home with hydration, rest, and simple remedies, while chronic or severe diarrhea may need medical attention.
• Preventing diarrhea involves good hygiene, careful food handling, and being aware of potential triggers that could upset your digestive system.

Diarrhea is a common but often disruptive problem that nearly everyone experiences at some point. While it’s usually a temporary issue, understanding its causes and knowing effective ways to find relief can help you manage symptoms and recover faster.

This article explores what diarrhea is, why it happens, and how to treat it at home. We’ll also discuss when it’s time to reach out to a doctor to avoid any potential complications.

Definition of diarrhea

Diarrhea refers to frequent, loose, or watery stools that occur more often than is normal for an individual. Diarrhea typically disrupts daily life for several days (acute episodes) to weeks (chronic episodes) in some cases.

It often causes significant discomfort and can lead to dehydration and even weight loss in more severe cases. Recognizing the difference between mild and severe cases is essential for effective management and can help prevent complications, especially in vulnerable populations like the elderly and young children.

Normal vs. abnormal diarrhea

Diarrhea, though uncomfortable, is often a normal reaction to something temporary, like a mild infection, a dietary change, or even stress.

Occasional diarrhea that goes away on its own in a day or two is common and usually not something to worry about. This kind of diarrhea can happen after trying a new or heavy food, feeling extra anxious, or catching a mild stomach bug. When symptoms are mild and brief, it generally means the body is handling the issue by clearing out irritants from the digestive system.

Abnormal diarrhea, which can signal an underlying issue, typically lasts longer, occurs more frequently, or is more severe in nature. If diarrhea continues for several days, recurs frequently, or is accompanied by red flags such as severe abdominal pain, fever, blood in the stool, or signs of dehydration, it’s considered abnormal and should be assessed by a doctor.

Chronic diarrhea lasting more than two weeks can point to digestive disorders, infections, or even systemic conditions like inflammatory bowel disease (IBD) or celiac disease. Recognizing when diarrhea is abnormal helps ensure timely treatment, which can prevent complications and address any root causes effectively.

Common causes of diarrhea

Diarrhea can result from various causes, each affecting the digestive system differently. The following are some of the most common causes:

Infections

Viral, bacterial, and parasitic infections are frequent culprits. Viruses like rotavirus and norovirus can lead to severe diarrhea, especially in young children, while bacteria like E. coli and Salmonella are often responsible for foodborne illnesses. In regions where sanitation is an issue, parasites may also be a risk factor, causing conditions like giardiasis, which can lead to persistent diarrhea if left untreated.

Food sensitivities and allergies

Some foods are harder for certain people to digest and can lead to diarrhea. Dairy products, for instance, contain lactose, which many people have trouble breaking down—a condition known as lactose intolerance. When someone with lactose intolerance consumes dairy, it can cause uncomfortable symptoms like gas, bloating, and diarrhea.

Gluten, a protein in wheat, can also trigger digestive issues in people with sensitivities. Additionally, food allergies, such as those to shellfish or nuts, may upset the stomach and lead to diarrhea and other gastrointestinal symptoms.

Medications

Certain medications disrupt the balance of bacteria in the gut or directly irritate the digestive system. Antibiotics, for example, can lead to antibiotic-associated diarrhea by reducing beneficial bacteria in the gut. Chemotherapy drugs and some types of antacids with magnesium are also common offenders.

Stress and anxiety

Stress can have a big impact on how well your digestive system works. When you’re stressed, your body’s hormones can change, causing your digestive system to speed up or slow down, which sometimes leads to diarrhea.

People who deal with high levels of stress or have anxiety disorders may often experience this as a “nervous stomach,” where digestive issues happen alongside feelings of anxiety.

Chronic health conditions

Certain long-term health issues, like Crohn’s disease, ulcerative colitis, and irritable bowel syndrome (IBS), often cause diarrhea as a main symptom.

These conditions lead to inflammation in the digestive system, making it hard for the body to absorb nutrients and water properly, which results in loose, frequent stools.

Common types of diarrhea

There are a few common types of diarrhea. Some are considered normal and others are a cause for concern.

Acute diarrhea

Acute diarrhea typically lasts for a few days and is often caused by infections (like viral gastroenteritis), food poisoning, or reactions to medications. It comes on suddenly and usually resolves on its own with hydration and rest. Acute diarrhea can be particularly disruptive but is generally temporary, though it requires close attention to avoid dehydration.

Persistent diarrhea

Persistent diarrhea lasts between two and four weeks and may be due to infections, dietary intolerances, or even mild chronic conditions. Unlike acute diarrhea, it may require further evaluation, especially if it doesn’t improve with home treatment. Tests might be needed to identify the root cause, such as food intolerances or parasitic infections.

Chronic diarrhea

Chronic diarrhea continues for four weeks or more and is often linked to underlying health issues, such as irritable bowel syndrome (IBS), Crohn’s disease, or celiac disease. This type can cause long-term health issues like nutrient deficiencies, so ongoing treatment and monitoring may be necessary.

Traveler’s diarrhea

Traveler’s diarrhea affects people visiting new places where water and food safety may differ from what they are used to.

It’s usually caused by consuming contaminated food or water and can lead to a range of symptoms, from mild discomfort to severe diarrhea. Preventing traveler’s diarrhea involves drinking bottled water, avoiding raw foods, and following strict hygiene practices while traveling.

Common symptoms of diarrhea

Diarrhea is often accompanied by other symptoms that can give clues about its cause and how intense it might be. Knowing these can help you decide the best ways to find relief and recognize if you need to see a doctor.

Frequent, loose stools

A primary sign of diarrhea is passing watery, loose stools more frequently than usual. This typically happens when the body isn’t absorbing water properly (often due to infections, certain foods, or irritants that upset the stomach).

Abdominal cramps and pain

Many people with diarrhea experience cramps or discomfort in their belly as the intestines contract to push things out quickly. This pain can range from mild to sharp and often improves once you’ve had a bowel movement.

Urgency to use the bathroom

With diarrhea, there’s often a sudden, strong need to find a bathroom, sometimes with little warning. This urgency happens because the intestines are more active, pushing waste through faster than usual, which can disrupt your day if diarrhea lasts a while.

Dehydration symptoms

Diarrhea can cause rapid fluid loss, leading to signs of dehydration, like feeling very thirsty, a dry mouth, dizziness, or feeling extra tired. Severe dehydration can become dangerous and may need medical attention, especially if you’re also feeling nauseous or vomiting.

Health risks of diarrhea

While diarrhea often goes away on its own, it can cause some health problems if it’s intense or persistent. Understanding these risks helps you know when it’s time to get additional help.

Dehydration

One of the most common issues with diarrhea is dehydration, which can get serious if fluids aren’t replaced quickly. Dehydration can lead to kidney problems, low energy, and even hospitalization, especially in older adults and young children.

Malnutrition

If diarrhea occurs for a long time, it can make it harder for the body to absorb important nutrients, leading to malnutrition (a lack of vitamins, minerals, and other essentials needed for health). This is especially a concern for people with conditions like Crohn’s disease or celiac disease, where the body struggles to take in enough vitamins and minerals. Without proper nutrition, the body may feel weaker and have a harder time healing and staying healthy.

Electrolyte imbalance

When fluids are lost, important electrolytes like sodium and potassium go with them. Electrolyte imbalances can cause weakness, heart rhythm problems, and, in severe cases, nerve issues. This makes it essential to replace lost fluids with something that has electrolytes.

How to treat diarrhea at home

Treating diarrhea at home focuses on simple but effective steps to manage symptoms and prevent complications. By following these strategies, you can often find relief and support your body’s recovery process.

Stay hydrated

Staying hydrated is crucial to avoid dehydration. Drinking water and electrolyte solutions, such as sports drinks or oral rehydration solutions, can help replace lost fluids and salts. Avoid sugary drinks and caffeine, as these can worsen symptoms.

Eat a bland diet

Starting with foods that are easy on the digestive system, like the BRAT diet (bananas, rice, applesauce, and toast), can help manage diarrhea. These foods are gentle on the stomach and can help firm up stools, reducing the frequency of bowel movements.

Get plenty of rest

Rest allows the body to focus on recovery. Physical activity should be limited until symptoms resolve, as excessive movement can aggravate the digestive system and prolong symptoms.

When to see a doctor about diarrhea

While diarrhea often resolves on its own, some signs indicate the need for professional medical attention.

You should see a doctor if:

• Diarrhea persists for more than two days without improvement.
• There is a small amount of blood or mucus in your stool.
• You experience symptoms of dehydration, like darker than usual urine, or dry mouth.
• You have a high fever (above 101°F or 38.3°C).

You should go to the emergency room if:

• You’re unable to keep fluids down for over 24 hours.
• You notice a moderate-large amount of blood in your stool.
• You experience severe abdominal pain that does not subside after a bowel movement.
• You feel extremely weak, dizzy, faint, or confused, as these may be signs of severe dehydration or an electrolyte imbalance.

Questions to ask your doctor about diarrhea

If you decide to seek medical advice for diarrhea, asking specific questions can help guide your treatment:

• What could be causing my diarrhea, and are there specific tests to identify the cause?
• Are there dietary changes I should make to help alleviate symptoms?
• What over-the-counter medications are safe to use for my situation?
• Should I avoid certain foods or drinks that may trigger further episodes?

How a doctor can help treat diarrhea

When at-home remedies aren't enough, a doctor can offer more targeted treatments to help relieve diarrhea and address any underlying causes. From medications to specific dietary recommendations, professional medical support can be crucial in more severe cases. Here are some ways a doctor might assist:

Prescription medications

For cases where over-the-counter options are ineffective, doctors may prescribe medications that slow intestinal movement or address specific symptoms, such as antispasmodic drugs for cramping.

IV fluids

If dehydration becomes severe, doctors may recommend intravenous (IV) fluids to help quickly restore fluids and keep you hydrated. IV fluids can also contain important electrolytes and minerals to correct any imbalances that might happen due to extended fluid loss from diarrhea.

Identifying and treating the underlying condition

If diarrhea is ongoing or persistent in nature, your doctor might order tests to find any underlying health issues, since treating these root causes can help prevent future episodes from occurring.

How to prevent diarrhea

While diarrhea can’t always be avoided, practicing certain habits can greatly lower your risk. Here are a few essential preventive steps:

Practice good hygiene

Washing hands thoroughly before meals and after using the bathroom can reduce the spread of germs that cause diarrhea. Good hygiene is particularly important when handling food or eating in shared spaces.

Be cautious with food and water

Avoid undercooked or raw foods, especially when traveling. Drinking bottled water in regions with poor sanitation and washing fruits and vegetables can reduce the risk of consuming harmful pathogens.

Manage stress

Since stress can impact digestive health, finding ways to manage stress, like regular exercise, meditation, or deep breathing exercises, can help maintain a healthy gut and reduce diarrhea episodes.

Frequently asked questions: diarrhea

After an episode of diarrhea, it’s normal to have questions about what to eat or drink to help restore balance in your digestive system. Here are some commonly asked questions to guide you through the recovery process and maintain digestive health going forward.

What can you eat or drink after experiencing diarrhea?

After experiencing diarrhea, your digestive system needs gentle foods and drinks to help it recover. Start with bland, low-fiber foods that are easy on your stomach, such as bananas, rice, applesauce, and toast (often called the BRAT diet).

These foods help firm up stools and provide essential nutrients without irritating the gut. Plain crackers, boiled potatoes, and clear broths are also great choices, as they’re easy to digest and won’t overload your digestive system. Avoid foods that are high in fat, spice, or sugar, as well as dairy products, which can worsen symptoms.

In addition to solid foods, staying hydrated is essential. Diarrhea leads to fluid and electrolyte loss, which can cause dehydration if not replenished. Aim to drink small sips of water regularly, and consider incorporating oral rehydration solutions like Pedialyte or electrolyte-infused water. Clear broths, herbal teas, and diluted fruit juices (without added sugars) can also help keep you hydrated while providing some nutrients. Once you’re feeling better, you can gradually reintroduce other foods, but keep monitoring your body’s response to avoid triggering symptoms again.

What if you have chronic diarrhea?

Chronic diarrhea, which lasts several weeks or recurs regularly, can be a sign of an underlying health condition.

Common causes of chronic diarrhea include irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) such as Crohn’s disease or ulcerative colitis, and food intolerances, like lactose or gluten intolerance. If you experience chronic diarrhea, it’s important to consult a healthcare provider for a proper diagnosis. They may recommend diagnostic tests, such as blood work, stool analysis, or even imaging, to pinpoint the underlying cause and develop an effective treatment plan.

Managing chronic diarrhea often involves dietary adjustments and, in some cases, medication. Your doctor may suggest an elimination diet to identify potential food triggers, such as dairy, gluten, or certain fruits and vegetables. Stress management techniques can also be helpful, especially if stress triggers your symptoms. If a specific condition like IBS or IBD is diagnosed, your doctor may prescribe medications to help control inflammation and manage symptoms. Regular follow-ups can help monitor your condition, adjust your treatment as needed, and maintain a better quality of life.

What if you’re pregnant and experiencing diarrhea?

Diarrhea during pregnancy is relatively common, often due to hormonal changes, prenatal vitamins, dietary adjustments, or even increased sensitivity to certain foods. While mild cases are usually manageable at home with hydration and rest, it’s important to be cautious, as dehydration can affect both you and your baby.

Avoid taking over-the-counter medications for diarrhea unless you’ve checked with your OBGYN first, as some medicines aren’t recommended during pregnancy. Instead, focus on keeping yourself hydrated by sipping on water, clear broths, or electrolyte drinks to help replace fluids you’ve lost. Eating simple foods, like plain rice, toast, or bananas, can also be easier on your stomach until you feel better.

Managing diarrhea

Diarrhea can be disruptive and uncomfortable, but with the right care and awareness, you can often manage it effectively at home. Staying hydrated, choosing gentle foods, and practicing good hygiene are key to preventing and relieving symptoms. However, knowing when to seek medical help is crucial, as prolonged or severe cases may indicate an underlying condition that needs attention.

General Medicine follows a strict editorial process, including using real experts to write our articles, vetted primary sources, fact-checking, a secondary medical review, and updates as necessary. This article was medically reviewed and fact checked by Dr. Lane Thaut, DO.

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