What should you know about diarrhea, heartburn and nausea?

Diarrhea, heartburn and nausea can occur together when digestive irritation, reflux, infection, medicines or food triggers affect different parts of the gut. Heartburn is a burning feeling behind the breastbone caused by stomach contents moving upwards; diarrhea means loose or watery stools; nausea is the urge to vomit. The combination does not identify one diagnosis by itself. The timing, severity, recent meals, new medicines and other symptoms help a clinician work out the likely cause.

A stomach or intestinal infection can cause nausea and diarrhea, while vomiting or irritation can make burning in the chest more noticeable. Reflux may happen after a large meal, lying down soon after eating, or eating foods that trigger symptoms. Inflammation of the stomach lining, such as gastritis, can also cause nausea, upper-abdominal discomfort and indigestion; read more about [Gastritis](/conditions/gastritis/).

Some medicines, alcohol, rich foods and food intolerance can upset digestion. Repeated reflux can be associated with [Acid Reflux](/conditions/acid-reflux/), and pressure around the opening in the diaphragm can contribute to symptoms in people with a [Hiatus Hernia](/conditions/hiatus-hernia/). Persistent upper-abdominal pain, vomiting or dark stools need medical assessment because conditions such as a [Peptic Ulcer](/conditions/peptic-ulcer/) can sometimes cause them.

Take frequent small sips of water or an oral rehydration drink, especially after each loose stool. Choose light foods as appetite returns, such as rice, toast, bananas or soup, and avoid alcohol, very fatty meals and foods that clearly worsen the burning. Smaller meals and staying upright after eating may reduce reflux. Do not stop a prescribed medicine without advice, but make a note of any new medicine or supplement that preceded the symptoms. A clinician or pharmacist can advise whether an [Acid Reflux Medication](/treatments/medical-management/acid-reflux-medication/) is suitable; diarrhea may make some self-treatment choices inappropriate.

Seek urgent medical help for severe or worsening abdominal or chest pain, trouble breathing, fainting, confusion, blood in vomit or stool, black tar-like stool, or signs of significant dehydration such as very little urine, a dry mouth and marked dizziness. Arrange prompt medical advice if you cannot keep fluids down, symptoms keep returning, diarrhea is persistent, or you have a fever or an ongoing change in bowel habits. People who are pregnant, older, immunocompromised or managing a serious long-term condition may need earlier advice.

Ask what pattern best fits your symptoms, whether a medicine or food could be contributing, and whether you need testing. Bring the start time, number and appearance of loose stools, the location of any pain, foods eaten recently, and a list of medicines and supplements. Mention whether heartburn follows meals or worsens when lying down, and whether nausea is accompanied by vomiting or reduced urination.