What Causes a Cough and Diarrhea Together?

Key takeaways:

• Your cough and diarrhea may be occurring due to two separate causes. This is likely if you noticed that one symptom began before the other
• There may be other symptoms in addition to your cough and diarrhea that can suggest a specific cause
• If you notice certain alarm features with your symptoms, you should seek further evaluation by a healthcare professional

Cough and diarrhea are two common but difficult symptoms to deal with. When you’re dealing with both of them at the same time, it can drastically reduce the quality of your life. If these symptoms persist for a long period, it can cause significant anxiety and frustration.

This article will discuss multiple causes of cough and diarrhea, treatment options you can try at home, and additional information that may help you determine whether you should seek further evaluation from a healthcare professional.

Are coughing and diarrhea related?

Sometimes, your cough and diarrhea may be related. However, they can also occur as separate symptoms from different causes.

If you notice that one of your symptoms began before the other or one resolves while you continue to deal with the other, it may suggest they were caused by different conditions. If you notice your symptoms started at a similar point and occurred simultaneously, they may be related to one single disease or condition.

Causes of cough and diarrhea

A cough can vary in duration, intensity, and associated symptoms, such as runny nose, shortness of breath, wheezing, or difficulty or pain with swallowing.

Diarrhea is defined as a change in bowel movements, also referred to as stools. Diarrhea is when your stool consistency becomes looser, in addition to having increased stool frequency. Diarrhea is defined as having more than three loose bowel movements each day. As seen in this Bristol stool chart, stools between types 5 and 7 can be classified as diarrhea. There are numerous causes of cough and diarrhea, and some of these specific causes will be discussed below.

Legionnaires’ disease

Legionnaires’ disease is caused by an infection of the bacteria Legionella. Legionnaires’ disease typically presents as pneumonia, meaning you may see associated symptoms like cough, fever, and shortness of breath.

However, Legionella can cause infections apart from the lungs, including cellulitis - an infection of the skin and soft tissues, which may progress to complications like abscesses, endocarditis (an infection of the inner lining of the heart), or meningitis (an infection of the membranes that surrounds the central nervous system).

Although infection with Legionella typically causes symptoms involving the lungs, it is also known to cause gastrointestinal symptoms, such as nausea, vomiting, and diarrhea. There are other additional features that are unique to Legionella infection that may help raise suspicion of this diagnosis, such as hyponatremia, a low level of sodium in your blood.

Adenovirus

Adenoviruses are a large family of viruses that can cause fevers and symptoms in young children. Similar to Legionella infection, it is most frequently associated with upper respiratory tract illnesses, and in more severe cases can lead to pneumonia.

Although it is less common, adenovirus can also cause diarrhea. In these cases, your infection may reflect gastroenteritis, which is inflammation of the GI tract. This can lead to symptoms of nausea, vomiting, and diarrhea. Although adenoviruses typically affect children, if you have recently been exposed to anyone with similar symptoms, adenovirus is one of the many infections that lead to both symptoms of cough and diarrhea.

Other infections

Numerous infections can lead to cough and diarrhea. It is possible that you may first experience symptoms of cough, runny nose, and other signs suggestive of an upper airway infection, with the development of diarrhea afterward.

This is usually a sign of gastroenteritis. Diarrhea and cough may occur at the same time, although in most cases, your diarrhea is typically delayed in onset relative to your cough.

Food sensitivities

If you notice that your symptoms began after ingestion of a specific food or group of foods, your symptoms may be due to a food sensitivity. Food sensitivities can develop at any point in life, even if you have previously been able to tolerate that food without any symptoms.

If you notice that you are experiencing symptoms like itchiness of your skin, mouth, or tongue, new rashes on your body, your cough and diarrhea may be representative of a food sensitivity. This may also be true in the case of more severe signs like swelling of the lips or throat, wheezing, or shortness of breath.

Causes of cough and diarrhea based on another symptom, condition, or situation

You may be experiencing other symptoms in addition to your cough and diarrhea. The presence or absence of these additional symptoms may help suggest a specific cause.

Cough and diarrhea with a fever

The presence of a fever with your cough and diarrhea may suggest a higher likelihood of infection as the underlying cause of your symptoms, although the lack of a fever does not exclude the possibility of infection.

Cough, congestion, and diarrhea

The presence of congestion in addition to your cough and diarrhea may suggest a previous upper respiratory infection, although congestion may also be suggestive of a mild allergic reaction or food sensitivity.

Cough, vomiting, and diarrhea

The presence of vomiting in addition to your cough and diarrhea may suggest an increased possibility of gastroenteritis.

Cough and diarrhea while pregnant

If you are pregnant, you may experience symptoms of cough and diarrhea. Although vomiting and nausea are typically seen in the first trimester, diarrhea may still occur throughout the course of pregnancy, and the presence of your cough may or may not be related to some of the other causes discussed.

Read our guides on different types of diarrhea and common causes of diarrhea for more.

How to treat a cough and diarrhea at home

In most cases, your cough and diarrhea may not be serious. Even so, it can be frustrating to deal with your symptoms. Here are some treatment options you can try at home that may help relieve your symptoms.

Fiber supplementation and other over-the-counter medications

Diarrhea can often be addressed by adding more fiber to your diet. Although there are numerous fiber supplements on the market, it is always better to get fiber from food.

There are numerous foods high in fiber content, such as beans, whole grains, various fruits, nuts, and legumes. Here is a comprehensive list of foods that are rich in fiber. There are also numerous over-the-counter medications that you can take that may help you with your diarrhea, such as Pepto-Bismol and Imodium.

Cough suppressants/Cough drops

If you notice that your cough is not improving, you can use cough-suppressing medications, such as Vicks, Robitussin, and other over-the-counter medications.

It is important to note that in many cases, cough can be a lingering symptom for many days to weeks. Other supportive care measures, such as cough drops, may also help with your symptoms.

Hydration

Whenever you are sick, hydration is an important treatment option. Fluid losses due to diarrhea make proper hydration particularly important.

Focus on taking small sips of water and electrolyte-containing fluids, such as Gatorade, light broths, soups, and other liquids that you can tolerate without making symptoms worse. Avoid foods that are extremely hot, acidic, spicy, and greasy, as these types of food may worsen your symptoms.

Read our guides on treating diarrhea at home for more.

When you should see a doctor for a cough and diarrhea

You may have tried some of the treatment options above but are still not improving. It may be time to seek medical attention. You should contact your doctor in the following cases.

You should see a doctor if:

• Your symptoms occur more frequently or the volume of your bowel movements continues to increase
• You notice weight loss
• You have significant changes in appetite
• You experience worsening abdominal pain
• You experience rectal bleeding or black, tarry stools
• You experience pain or diarrhea during the night
• You have a first-degree relative with IBD or colorectal cancer
• You notice the development of mucus or phlegm with your cough

You should go to the emergency room if:

• You vomit blood
• You notice bright red blood in your bowel movements
• You experience loss of control of your bladder or bowel
• You experience sudden dizziness that does not resolve
• You experience ongoing palpitations - the sensation of a racing heart
• You experience shortness of breath
• You are unable to tolerate anything by mouth, including fluids

Questions to ask your doctor about a cough and diarrhea

• Is there a need to obtain blood work, sputum cultures, urine or stool studies, or other lab work to assess your symptoms?
• Is there a need to obtain any imaging, such as CXR, ultrasound, CT, or MRI?
• Is there a need to obtain an endoscopy: esophagogastroduodenoscopy (EGD) or colonoscopy?
• What other treatment options or medications may help address your symptoms?

Frequently asked questions: cough and diarrhea

Cough and diarrhea are common symptoms, and they can be frustrating even when experiencing them individually, let alone when you’re experiencing both at the same time. Some frequently asked questions about cough and diarrhea are discussed below.

Are cough and diarrhea a sign of COVID?

Cough and diarrhea can occur due to various infections, including COVID. If you have recently been around someone with similar symptoms, it increases your risk of having an infection, including COVID.

What should you eat or drink if you have a cough and diarrhea?

When experiencing cough and diarrhea, eating and drinking fluids that do not worsen your symptoms is important. Avoiding potentially triggering foods and focusing on hydration is important.

Understanding your symptoms

Cough and diarrhea can have multiple causes, and sometimes these symptoms are related to the same cause. Understanding your symptoms and when to reach out to your primary care provider can help reduce the duration and severity of your symptoms, in addition to preventing any potential complications.

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. Pallabi Sanyal-Dey, MD.

Sources

Irwin, Richard S et al. “Classification of Cough as a Symptom in Adults and Management Algorithms: CHEST Guideline and Expert Panel Report.” Chest vol. 153,1 (2018): 196-209. doi:10.1016/j.chest.2017.10.016

Lomer, M C E. “Review article: the aetiology, diagnosis, mechanisms and clinical evidence for food intolerance.” Alimentary pharmacology & therapeutics vol. 41,3 (2015): 262-75. doi:10.1111/apt.13041

Robyn. “Bristol Stool Chart.” Continence Foundation of Australia, 9 Feb. 2024, www.continence.org.au/bristol-stool-chart.

Top High-Fiber Foods to Help Your Digestive Health. 1 Jan. 2000, www.benefiber.com/fiber-in-your-life/daily-fiber-intake/top-10-high-fiber-foods.