Gastroenteritis – Vomiting and/or Diarrhea


What are some infectious causes of vomiting and diarrhea (gastroenteritis)?

Below are some of the most common causes of acute gastroenteritis: 

  • Bacteria, viruses and parasites (eg. Salmonella, staphylococcus, clostridium difficile, norovirus, and giardia lamblia are common locally)
  • Travel – “traveller’s diarrhea” is usually caused by an e. coli bacteria that we’re not used to.

How does it spread?

  • Food contamination
  • Direct contact with an infected person
  •  Contact with surfaces that an infected person has touched

Note: some germs and viruses that cause vomiting and diarrhea are resistant to alcohol hand gels! Therefore it is important to use hand-washing instead of alcohol-based hand sanitizers. 

Should I be seen in the office?

Most people with acute gastrointestinal conditions don’t benefit from an office visit, but are potentially infectious and dangerous to vulnerable staff and other patients. Antibiotics are rarely indicated.

Please consider the following information before booking an appointment.

What should I do if I have vomiting and/or diarrhea?

  • Stay home and rest. Most cases of vomiting last less than 24 hours, and for diarrhea, less than 5 days. The biggest risk is dehydration through fluid loss. See section
    “Dehydration Prevention.”
  • Wash your hands frequently to prevent spreading it to others
  • Call our office if you have new or worsening symptoms or your illness lasts longer than a few days.

Dehydration Prevention and Treatment

Signs of dehydration: 

  • Dark urine or infrequent urination
  • Dry mouth, tongue or eyes
  • Thirst
  • Muscle cramps
  • Dizziness or confusion

To prevent/treat dehydration:

  • Drink half strength apple juice
  • If you are persistently unable to tolerate fluids by mouth (24 hours or longer), intravenous fluids may be necessary in severe cases
  • The ability to digest milk might be reduced temporarily and should be avoided

What can I do to feel better? 

  • Drink lots of fluids, if possible
  • Try eating foods that have lots of fluid in them (eg. soup, jell-o, and popsicles). If you do OK with those foods, try soft bland foods (eg. bread, rice, oatmeal, or saltine crackers). Avoid foods high in fat and sugar.
  • Avoid strong smells, like perfume
  • Medicines such as loperamide (brand name: Imodium) or bismuth subsalicylate (Pepto-Bismol) may help ease persistent diarrhea.

Call for advice if you take other medications or you have conditions on the list under “When to call the CRFHT”.

What can I do to prevent vomiting/diarrhea?

  • Wash your hands with soap and water, especially after: changing diapers, going to the bathroom, touching animals, and being in public places.
  • Keep your hands away from your face and avoid eating finger foods until you’ve had a chance to wash
  • Stay home from school or work until you feel better
  • Pay close attention to food safety
  • Have your baby vaccinated with the rotavirus vaccine

Medical Treatment

In the majority of cases, patients do not need treatment for acute vomiting or diarrhea because symptoms will get better on their own. However, people with dehydration not responding to home treatment should call our office for advice. 

When to call the CRFHT

  • Persistent high fever (above 100.4ºF or 38ºC)
  • Bloody diarrhea or vomit
  • Severe chest or belly pain
  • Signs of persisting dehydration
  • Over the age of 70 years or under 3 years
  • If you are pregnant
  • If you have diabetes
  • A history of inflammatory bowel disease, cardiac disease, or an immunodeficiency-causing disease
  • Symptoms lasting more than 5 days
  • Recent travel outside of Canada and the US
  • Employees of: day care centres, healthcare workers, food handlers

 If you do make an appointment…

Please remember to wash your hands before you arrive at the clinic and after using the toilet with warm soap and water 

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