According to the Centers for Disease Control and Prevention (CDC), over 35 million Americans each year seek medical attention after experiencing symptoms related to the digestive system. While most of these gastrointestinal symptoms are common, how they manifest can differ wildly from person to person depending on the underlying cause. Two examples of common symptoms—having an upset stomach with diarrhea—sometimes present together and often leave the person feeling weak and dehydrated. Each symptom has a variety of possible causes behind it, but why do they sometimes happen simultaneously? And when are the symptoms severe enough to require medical attention?

Understanding the Symptoms

When someone says they have an upset stomach, they’re typically referring to a disorder of digestive function that involves abdominal pain or discomfort and other related symptoms like nausea, heartburn (acid reflux), or bloating. This disorder, also known as indigestion or dyspepsia, is quite common in the general population and is most often experienced as a functional condition; in other words, there is no obvious evidence of an underlying disease. Symptoms of an upset stomach can range from mild to severe, but for most people it is a minor and temporary inconvenience.

In some cases, a person with an upset stomach will also develop diarrhea, another common gastrointestinal symptom. Diarrhea is usually defined as having at least three loose, liquid, or watery bowel movements each day. Acute diarrhea is a common problem that typically lasts one or two days and goes away on its own, while persistent diarrhea lasts longer than two weeks and less than four weeks, and chronic diarrhea lasts at least four weeks. Even though these two conditions on their own are usually minor concerns, the combination of the two sets of symptoms can lead to more significant health problems.

What Causes an Upset Stomach With Diarrhea?

There are a variety of factors that can lead to having either an upset stomach or diarrhea, and many of those factors overlap for both conditions. Below are some of the most common causes of both sets of symptoms happening simultaneously:

    • Viral infection: Exposure to viruses like rotavirus or norovirus are a common cause of both an upset stomach and diarrhea. An infection from one of these viruses often leads to gastroenteritis, an inflammation of the stomach lining. Viral gastroenteritis is also often erroneously referred to as the stomach flu.
    • Bacterial infection: Bacterial infections that can cause an upset stomach and diarrhea include Salmonella, E. coli, and Campylobacter. Bacterial infections can also lead to gastroenteritis, and they are often caused by exposure to contaminated food or water sources.
    • Parasites: Another category of pathogens that can lead to an upset stomach and diarrhea is parasites. When species like Giardia and Cryptosporidium enter the digestive tract, they can cause the lining of the stomach to become irritated and inflamed. In addition to stomach pain and diarrhea, symptoms include fatigue, weight loss, and nausea.
    • Food poisoning: Food poisoning, or foodborne illness, encompasses any illness that comes from food that has been contaminated. This includes viruses, bacteria, and parasites, as well as fungi and any other kind of toxin. Depending on the type of toxin, food poisoning can also lead to an upset stomach, diarrhea, and a host of other symptoms.
    • Food intolerance: Food intolerance is a medical condition that involves difficulty in digesting certain foods or ingredients in food. Eating a food you’re intolerant to usually isn’t serious, but it can make a person feel unwell. Both diarrhea and an upset stomach are common symptoms, but an intolerance can also cause other gastrointestinal symptoms. One of the most common examples around the world is lactose intolerance, which is an inability to process the protein lactose that is found in dairy products.
    • Digestive diseases: There are also various digestive diseases that include stomach aches and diarrhea; one relatively common example is irritable bowel syndrome (IBS), a collection of symptoms that is thought to be caused by a number of different factors. Another example is inflammatory bowel disease (IBD), a condition characterized by inflammation of the intestinal lining; the two principal diseases of IBD are Crohn’s disease and ulcerative colitis.
    • Stress: Perhaps surprisingly, stress from one’s lifestyle can also lead to gastrointestinal symptoms like an upset stomach and diarrhea. When you're stressed, your body releases cortisol and adrenaline, which can slow down your digestive system and make it harder to digest and absorb food. Stress can also cause your body to divert blood flow away from your gut and toward your muscles, which can make it harder for your digestive system to work properly. The impact of stress on the digestive system is believed to be related to the gut-brain axis, the series of neural pathways that travel between the brain and the digestive tract.
    • Celiac disease: Celiac disease is a chronic digestive and immune system disorder that is triggered by eating foods containing gluten, a protein found in wheat, barley, and rye. When gluten is consumed, an inflammatory response from the immune system leads to a variety of symptoms like indigestion, diarrhea, stomach cramps, and constipation.
    • Alcohol: While modest alcohol consumption can be safe for some people, excessive use can affect the digestive system in a number of ways. Among other effects, alcohol can irritate and inflame the lining of the stomach, leading to both stomach problems and bowel motility problems.

    How to Soothe an Upset Stomach With Diarrhea

    Apart from the rare case of having severe abdominal pain or severe diarrhea, the treatment of these symptoms can generally be achieved with some lifestyle changes and adjustments to one’s diet. Below are some Dos and Don’ts for how to relieve an upset stomach with diarrhea:

    Do:

      • stay hydrated by drinking plenty of fluids like water, clear broth, or sports drinks that contain electrolytes
      • consume foods with probiotics like yogurt and pickles
      • drink peppermint or chamomile tea
      • use (in consultation with a doctor) over-the-counter medications that can help control diarrhea

      Don’t:

      • eat foods that are spicy, greasy, fatty, or high in fiber
      • drink alcohol or caffeine since they can irritate the digestive tract
      • use antibiotics unless prescribed by a doctor because of their potential impact on the gut microbiome

      When to Speak With a Gastroenterologist

      In most cases, an upset stomach with diarrhea will get better on its own within a few days or a week. If it takes longer than that to improve, it may be an indicator of another problem. Other symptoms to look out for: blood in the stool, high fever, or signs of dehydration. If any of these symptoms are present in addition to persistent stomach problems and diarrhea, seek out a healthcare provider as soon as possible. At Cary Gastro, we are passionate about providing excellent digestive care so that you can maintain a high quality of life. To speak to a gastroenterologist about any of your symptoms, please contact us today to request an appointment.