Stomach Pain and Diarrhea: What Usually Causes It and What to Watch For

Stomach pain and diarrhea are a very common symptom combination. In many cases, the cause is short-term and improves on its own, such as a stomach virus, food poisoning, or mild digestive irritation. But sometimes these symptoms can point to dehydration, bacterial infection, inflammatory bowel disease, or another condition that needs medical care.

If you are experiencing stomach pain and diarrhea right now, try our symptom checker for a personalized assessment.

Common Causes of Stomach Pain and Diarrhea

Viral Gastroenteritis

A stomach virus is one of the most common causes of abdominal cramping, diarrhea, nausea, and fatigue. Symptoms usually improve over a few days but can leave you dehydrated if you cannot keep fluids up.

Food Poisoning

Food poisoning often causes sudden stomach pain, diarrhea, nausea, vomiting, and sometimes fever. Symptoms may start within hours after eating contaminated food.

Irritable Bowel Syndrome (IBS)

IBS can cause cramping, bloating, diarrhea, or alternating diarrhea and constipation. Symptoms often flare with stress or certain foods.

Medication Side Effects

Some medications, especially antibiotics and certain supplements, can irritate the stomach and trigger diarrhea and abdominal discomfort.

Food Intolerance

Lactose intolerance and other food sensitivities can cause stomach pain, gas, bloating, and diarrhea after eating trigger foods.

More Serious Causes

Most cases are not emergencies, but some need prompt evaluation.

Dehydration

Frequent diarrhea can quickly lead to dehydration, especially in children, older adults, and anyone who is also vomiting.

Bacterial Infection

If diarrhea is severe, bloody, or comes with high fever, a bacterial cause becomes more concerning.

Inflammatory Bowel Disease

Crohn disease and ulcerative colitis can cause abdominal pain, diarrhea, fatigue, and sometimes blood in the stool.

Appendicitis or Other Abdominal Emergency

Severe or localized abdominal pain, especially if it gets worse over time, is not something to ignore even if diarrhea is also happening.

Red Flags

Get medical help urgently if you have:

• blood in the stool
• black stool
• severe or worsening abdominal pain
• high fever
• fainting or confusion
• signs of dehydration
• persistent vomiting
• symptoms lasting longer than expected

What You Can Do at Home

If there are no red flags, it may help to:

• drink water or electrolyte fluids often
• eat bland foods in small amounts
• avoid greasy, spicy, or dairy-heavy foods for a bit
• rest
• avoid alcohol
• pay attention to whether a certain food or medication triggered symptoms

When to See a Doctor

See a doctor if:

• symptoms last more than a few days
• diarrhea is frequent or severe
• abdominal pain is worsening
• you cannot stay hydrated
• symptoms keep recurring
• you suspect IBS, IBD, or food intolerance

Bottom Line

Stomach pain and diarrhea are often caused by viral gastroenteritis, food poisoning, IBS, food intolerance, or medication side effects. But dehydration, blood in the stool, high fever, or severe pain are signs to take seriously.

Use our symptom checker to better understand what might be causing your symptoms and what next step makes sense.

This article is for educational purposes only and does not replace professional medical advice.