Parasitic gastroenteritis is a form of gastrointestinal inflammation caused by a parasite. There are different types of parasitic infections that can lead to this form of gastroenteritis, but each one can cause uncomfortable — and sometimes serious — symptoms.

Read on to learn about the causes and symptoms associated with parasitic gastroenteritis, and how it may be treated and prevented.

The term “gastroenteritis” refers to inflammation of the digestive tract. Gastroenteritis may be caused by:

Parasitic gastroenteritis is caused by an infection of the gastrointestinal tract from parasites. The two most common parasites that cause parasitic gastroenteritis are Cryptosporidium and Giardia.

Cryptosporidium is spread through drinking water and recreational sources of water, such as pools, and is a common cause of waterborne illnesses.

Giardia is transmitted through water as well as through contaminated soil and food. This contamination can come from the feces of an animal or a human carrying the infection.

Both of these parasites are resilient due to strong outer shells that allow them to survive certain conditions for a long time.

You may be at a higher risk of exposure to these parasites if you:

  • travel internationally, especially to areas with improper sanitation
  • do not wash your hands or food properly before food preparation or eating
  • are a young child or an older adult
  • are immunocompromised
  • work in a day care setting or an assisted living facility
  • eat undercooked or raw meats

Due to a wide range of uncomfortable symptoms, gastroenteritis is often known by the misnomer “stomach flu.” Symptoms of parasitic gastroenteritis may develop over the course of 1 to 2 weeks and typically last for several days.

Some of the most common symptoms of parasitic gastroenteritis include:

It’s best to contact a doctor right away if you:

  • have symptoms that do not improve after 2 or 3 days
  • start experiencing delirium
  • feel seriously dehydrated
  • see blood in your stool

These symptoms may indicate a more severe case that could require additional medical treatment.

While parasitic gastroenteritis alone may resolve on its own in some people, others may need medications to help treat the underlying infection. Doctors may prescribe medications such as albendazole or metronidazole for this condition.

Additionally, a doctor may recommend antidiarrheal medications, such as nitazoxanide. This may also help reduce the risk of dehydration and related complications.

First, a doctor will need to determine the type of parasite that’s causing gastroenteritis. This is typically done via fecal testing, where a stool sample is taken and examined under a microscope.

Before treatment, a doctor may also need to rule out other conditions that may cause similar symptoms, such as:

Certain groups of people may be at a higher risk of a severe case of parasitic gastroenteritis, including:

  • children
  • older adults
  • those who are immunocompromised

Dehydration is another potential complication of parasitic gastroenteritis due to the loss of body fluids and electrolytes from diarrhea, vomiting, and reduced water and food intake. Children are the most vulnerable because of their smaller size.

Dehydration from parasitic gastroenteritis may develop quickly and become a life threatening situation. If you or a loved one is experiencing dehydration, get medical help right away.

Signs of dehydration may include:

  • dark-colored urine
  • fatigue
  • headache
  • poor concentration
  • disorientation or dizziness
  • dry lips, mouth, and skin
  • weak or rapid pulse
  • heart palpitations

Severe dehydration may require hospitalization. If you’re hospitalized, a doctor will likely give you intravenous (IV) fluids to help restore water and electrolyte balances in your body.

One of the best ways to prevent parasitic gastroenteritis is to practice good handwashing habits. Overall, you can reduce your risk of this type of gastroenteritis by:

  • washing your hands before eating and drinking, before preparing food, and after using the bathroom
  • frequently washing your hands when you’re at work or school
  • washing fruits and vegetables properly when preparing meals
  • cooking all foods, particularly raw meats, to the proper temperature
  • avoiding areas that are known to have parasites
  • supporting your gut health with digestive enzymes and probiotics, but only if a doctor recommends them

Parasitic gastroenteritis is a type of gastrointestinal inflammation that’s caused by parasites. It’s spread through contaminated soil, food, and water that’s been in contact with feces of an animal or person.

While some cases of parasitic gastroenteritis resolve on their own without treatment, you should call a doctor if your symptoms persist beyond a few days. A doctor can give you an accurate diagnosis and rule out other conditions that cause similar symptoms.

Some people may need medication to treat the underlying parasitic infection and to ease the symptoms of diarrhea.

Severe dehydration is a potential complication of parasitic gastroenteritis and is considered a medical emergency that may require hospitalization and IV fluids.