Causes of nausea and diarrhea
Pro Research Analysisby 
Searched over 200M research papers
Common Causes of Nausea and Diarrhea
Nausea and diarrhea are frequent symptoms that can result from a variety of underlying causes. The most common cause is gastroenteritis, which is an inflammation of the gastrointestinal tract often triggered by infections. These infections can be due to bacteria, viruses, or parasites and are a leading reason for both nausea and diarrhea in children and adults 3568.
Infectious Agents: Bacteria, Viruses, and Parasites
Infectious diarrhea is commonly caused by bacteria such as Salmonella, Shigella, and Escherichia coli, as well as viruses and parasites. These pathogens can be transmitted through contaminated food, water, or person-to-person contact. Infections often present with additional symptoms like vomiting, abdominal pain, and sometimes fever. Polymicrobial infections (infections with more than one microorganism) are also common and can increase the likelihood of nausea and abdominal pain 568.
Food Poisoning and Toxins
Certain bacteria, such as Bacillus cereus, can cause food poisoning. This bacterium produces toxins that lead to two types of illness: one type causes nausea and vomiting, while the other leads to diarrhea and abdominal pain. The specific symptoms depend on the type of toxin produced by the bacteria .
Gastrointestinal Food Hypersensitivity and Allergies
Food allergies and hypersensitivity reactions can also cause gastrointestinal symptoms, including nausea, vomiting, abdominal pain, and diarrhea. These reactions are typically due to immediate hypersensitivity mechanisms in the gut .
Rare and Specific Medical Conditions
Some rare conditions, such as eosinophilic gastroenteritis, can present with nausea, vomiting, and diarrhea. This disease involves abnormal infiltration of eosinophils (a type of white blood cell) in the gastrointestinal tract and is not related to infections or parasites .
Post-Surgical and Rapid Gastric Emptying
Nausea and diarrhea can also occur after certain surgical procedures, such as ileogastrostomy. In some cases, infection with Helicobacter pylori has been linked to severe post-surgical nausea and diarrhea, and treating the infection can resolve these symptoms . Additionally, rapid gastric emptying (either idiopathic or post-surgical, as seen in dumping syndrome) can cause chronic nausea and diarrhea, sometimes accompanied by other symptoms like abdominal pain and hypoglycemia .
Non-Infectious and Other Causes
Non-infectious causes of nausea and diarrhea include gastrointestinal bleeding, adrenal insufficiency, thyroid storm, mesenteric ischemia, toxic exposures, and acute radiation syndrome. These are less common but important to consider, especially if infectious causes are ruled out .
Conclusion
Nausea and diarrhea are most often caused by infections (bacterial, viral, or parasitic), food poisoning, or food hypersensitivity. Less commonly, they may result from rare diseases, post-surgical complications, or non-infectious medical conditions. Identifying the underlying cause is important for effective treatment and management 1234+5 MORE.
Sources and full results
Most relevant research papers on this topic