A stomach virus can cause severe dehydration due to excessive vomiting and diarrhea. While many people can prevent it through oral fluid management, some may need intravenous (IV) fluids.

A stomach virus, or gastroenteritis, is often referred to as “stomach flu.” People typically experience moderate to severe vomiting and diarrhea.

When a person has these symptoms for a long period of time, they can become dehydrated, particularly if they cannot keep any oral fluids down.

Dehydration can become life threatening and may require IV fluid to correct.

A person in hospital having had IV fluids to treat stomach virus.Share on Pinterest
Leah Flores/Stocksy

A stomach virus typically refers to gastroenteritis. While people often call the infection “stomach flu,” it is neither related to seasonal flu, nor does it occur in the stomach. Instead, the virus infects the intestines.

However, a stomach virus causes several symptoms that affect a person’s gut. Doctors consider the infection acute, meaning it appears and resolves quickly. Most cases last no longer than 1 week and will typically clear without medical intervention.

In some cases, it can lead to dehydration, a potentially fatal complication.

When viral gastroenteritis occurs, it typically causes symptoms such as:

  • watery diarrhea
  • fever in some people
  • vomiting
  • nausea
  • cramping or pain in the abdomen

People often recover from the infection with no major issues. However, if they are unable to keep fluids down or drink enough, it can lead to dehydration, which can be fatal. Signs and symptoms of dehydration may include:

  • feeling tired or fatigued
  • extreme thirst
  • headaches
  • less frequent or lower amount of urine
  • dark-colored urine
  • feeling faint or lightheaded
  • sunken cheeks or eyes
  • chapped or cracked skin on the lips
  • skin lacks usual elasticity

Doctors generally recommend a person use oral fluids to help prevent dehydration during the infection. This is typically the first line of defense against dehydration.

A person should use sports drinks or other non-caffeinated drinks to replenish liquid and electrolytes.

Oral fluid replacement often works for mild cases of dehydration associated with viral gastroenteritis. However, if symptoms of dehydration worsen, a person should consult a doctor as soon as possible.

A doctor may recommend IV fluids in the hospital in cases of severe dehydration.

IV fluids will not directly help with a stomach virus. The virus needs to resolve on its own, typically within 1 week.

In some cases, a doctor may administer antinausea or diarrhea medication directly to a person’s bloodstream. This does not make the virus go away but may help alleviate symptoms.

Otherwise, IV fluids can help rehydrate a person with moderate to severe dehydration.

IV therapy does not cure a stomach virus. It is used in cases of severe dehydration associated with the virus and, in some cases, delivers medications that may help with symptoms.

According to the Centers for Disease Control and Prevention (CDC), experts recommend using Ringer’s lactate solution to help replace fluids and electrolytes in the blood.

More standard saline or dextrose solutions can also work if this is unavailable. The CDC also recommends that a person should drink, if possible, even once the IV drip has started.

A person should contact a doctor if they have concerns that they or someone else are experiencing dehydration.

A primary care doctor can diagnose dehydration and admit the person for treatment in the hospital if necessary.

The amount of time it takes for IV fluids to work can vary. The CDC recommends healthcare staff check a person’s hydration levels every 15–30 minutes.

Once a person has rehydrated, they recommend switching from IV fluids to oral solutions.

Home healthcare has increased in recent years. Doctors may prescribe it for conditions such as:

  • replacing nutrients
  • antibiotic delivery
  • pain relief management
  • hormone deficiency treatment

While a doctor may diagnose and prescribe IV fluids for home use, it is more likely they will recommend hospital treatment. Currently, the recommendation for treatment for dehydration occurs at the hospital.

Treatment for a stomach virus is limited.

For both children and adults, the most important part of treatment is keeping fluids up by drinking juice, sports drinks, or other noncaffeinated liquids.

Adults may use over-the-counter (OTC) medications, such as loperamide or bismuth subsalicylate to help with their symptoms as the virus runs its course.

Parents and caregivers should talk with a pediatrician before giving any OTC medications to children.

A person should consult a doctor if they notice signs of dehydration in themselves or their children. A doctor can diagnose dehydration and recommend treatment.

A person should also consider seeing their doctor if the symptoms of a stomach virus last longer than 1 week.

A stomach virus can cause severe dehydration due to excessive vomiting and diarrhea. Some people may need IV fluids to correct it.

IV fluids do not treat a stomach virus directly. Instead, a doctor prescribes them to treat moderate to severe dehydration. In some cases, they may also administer medication to reduce symptoms of the infection.