Stomach Flu: A Simple Guide for Everyone

What Are the Symptoms of Stomach Flu?

When you have stomach flu, you may feel sick to your stomach (nausea), throw up (vomit), have diarrhea, stomach pain, fever, and body aches. These symptoms usually start 1 to 2 days after you catch the virus.

Stomach flu makes you feel unwell in your stomach and gut. The medical name for stomach flu is gastroenteritis. It is not the same as the regular flu, which affects your lungs and breathing. Stomach flu affects your stomach and intestines.

The symptoms can be mild or more severe. Some people only feel a little sick. Others may throw up many times and have frequent diarrhea. Children often throw up more, while adults often have more diarrhea. Most people start to feel better after 1 to 2 days.

Here are the common symptoms of stomach flu:

• Feeling sick to your stomach (nausea). You may feel like you want to throw up.
• Throwing up (vomiting). This may happen several times a day.
• Diarrhea. Loose, watery stools that happen often.
• Stomach pain. Cramps or general pain in your belly.
• Fever. Usually a mild fever, not very high.
• Body aches. Feeling tired and sore all over.
• Not wanting to eat. This is normal when your stomach is upset.

Signs of Dehydration

When you throw up and have diarrhea, your body loses water. This is called dehydration. Dehydration can be serious, especially in babies, young children, and older adults. It is important to know the signs so you can act quickly.

Watch for these signs of dehydration:

• Very thirsty. You feel you need to drink a lot.
• Dry mouth. Your mouth and lips feel dry.
• Not urinating much. You don't pee as often as normal, or your urine is dark yellow.
• Feeling dizzy. You feel lightheaded when you stand up.
• Tired or weak. You have less energy than normal.

What Causes Stomach Flu?

Stomach flu is caused by viruses. The most common virus is called norovirus. You can catch it from other people who are sick, from contaminated food or water, or by touching surfaces that have the virus on them.

Viruses cause most cases of stomach flu. These viruses are very easy to catch. You only need to be around a tiny amount of the virus to get sick. This is why stomach flu spreads so easily in families, schools, and workplaces.

The main viruses that cause stomach flu are:

• Norovirus. This is the most common cause in adults and older children. It is sometimes called the "winter vomiting bug" because it is more common in winter.
• Rotavirus. This used to be the most common cause in young children. A vaccine now protects many children from this virus.

Bacteria can also cause stomach flu, but this is less common. Bacterial infections are often linked to eating contaminated food. This is sometimes called food poisoning.

How Does Stomach Flu Spread?

Stomach flu spreads very easily from person to person. The virus leaves your body in your vomit and stool (poop). If even a tiny amount gets into another person's mouth, they can get sick too.

Here are the main ways stomach flu spreads:

• Touching someone who is sick. Or sharing food, drinks, or utensils with them.
• Eating contaminated food. Food prepared by someone who is sick can make you sick.
• Touching contaminated surfaces. Door handles, phones, and bathroom surfaces can carry the virus.
• Being near someone who is vomiting. Tiny particles can spread through the air.

What Can I Do at Home to Feel Better?

The most important thing is to drink more fluids than usual. Take small sips often. Rest your stomach by not eating solid food while you are vomiting. When you feel ready to eat, start with simple, bland foods like crackers or toast.

Most people with stomach flu do not need to see a doctor. The illness goes away on its own in 1 to 3 days. The key is to keep drinking fluids so you do not become dehydrated. Your body needs water to work properly, and you lose a lot of water when you throw up and have diarrhea.

Since stomach flu is caused by viruses, antibiotics will not help. Antibiotics only work against bacteria, not viruses. Your body will fight off the virus on its own. You just need to rest and stay hydrated.

How to Stay Hydrated

Drinking fluids is the most important part of treatment. But how you drink matters too. If you drink too much at once, you might throw up again. The best way is to take small sips every few minutes.

Good drinks when you have stomach flu:

• Water. The simplest choice. Drink small sips often.
• Oral rehydration solution. You can buy this at a pharmacy. It has the right mix of water, sugar, and salts that your body needs.
• Clear broth. Chicken broth or vegetable broth can be soothing and give you some salt.
• Diluted juice. Mix half juice with half water. Straight juice has too much sugar.
• Ice chips or popsicles. These can help if drinking is hard.

Drinks to avoid: Do not drink milk, coffee, alcohol, or undiluted fruit juice. These can make your symptoms worse.

What to Eat

When you are throwing up, do not try to eat solid food. Wait until the vomiting stops for a few hours. Your stomach needs time to rest and recover.

When you feel ready to eat again, start with small amounts of simple, bland foods:

• Plain crackers.
• Dry toast.
• Bananas.
• Plain white rice.
• Applesauce.

Foods to avoid at first: Stay away from dairy products (milk, cheese), fatty or fried foods, spicy foods, and raw vegetables until you feel much better.

Caring for Babies and Young Children

Babies and young children can become dehydrated faster than adults. They need extra attention when they have stomach flu.

If your baby is breastfeeding, continue to breastfeed. Offer the breast more often than usual. Breast milk is easy to digest and helps fight the infection.

For older children, give them oral rehydration solution. You can find child-friendly versions at the pharmacy. Give small amounts often using a spoon or syringe if they don't want to drink from a cup. You can also try popsicles made from oral rehydration solution.

When Should I See a Doctor?

See a doctor right away if you have blood in your vomit or stool, cannot keep any fluids down for more than 24 hours, have very severe stomach pain, show signs of serious dehydration, or have a very high fever. Babies under 6 months should always be seen by a doctor.

Most people with stomach flu get better at home without needing to see a doctor. The illness usually goes away on its own in a few days. However, some situations need medical attention.

It is important to know when to seek help. If you are not sure, it is always better to call a healthcare provider and ask for advice than to wait too long.

When to Get Help for Children

Children, especially young children and babies, need extra attention. They can become dehydrated more quickly than adults.

Get medical help for a child if:

• A baby under 6 months has vomiting and diarrhea.
• A baby has no wet diapers for 6-8 hours.
• A child cries without tears.
• A child is very drowsy or hard to wake up.
• A child has blood in their vomit or stool.
• A child has high fever with shaking (chills).

How Can I Stop Stomach Flu from Spreading?

Wash your hands often with soap and water, especially after using the bathroom and before eating or preparing food. Clean surfaces like toilets and door handles. Do not prepare food for others while you are sick. Stay home until at least 2 days after your symptoms stop.

Stomach flu is very contagious. It spreads easily to other people. The virus can live on surfaces for days. Good hygiene is the best way to stop the spread.

Washing your hands is the most important thing you can do. Soap and water work better than hand sanitizer against the viruses that cause stomach flu. Make sure to wash for at least 20 seconds.

Tips to Prevent Spreading Stomach Flu

• Wash your hands often. Use soap and water. Wash after using the bathroom, before eating, and before preparing food.
• Clean surfaces. Use a cleaning product with bleach to clean toilets, door handles, phones, and other surfaces.
• Wash laundry in hot water. Wash clothes, towels, and bedding that may have the virus on them.
• Stay home. Do not go to work, school, or other places while you are sick. Stay home for at least 2 days after you feel better.
• Do not prepare food for others. Wait 2-3 days after your symptoms stop before cooking for other people.
• Use your own towel. Do not share towels or utensils with others while you are sick.

What Medical Treatments Are Available?

Most people do not need any medical treatment for stomach flu. If you are very dehydrated, a doctor may give you fluids through a tube in your arm (IV). Antibiotics are only used if a doctor finds that bacteria, not a virus, caused your illness.

For most people, the only treatment needed is rest and drinking fluids at home. The stomach flu will go away on its own. But sometimes medical treatment is needed, especially for severe cases.

Treatments a Doctor May Give

IV fluids. If you are very dehydrated and cannot drink enough, a doctor may give you fluids directly into your blood through a small tube in your arm. This quickly puts water and salts back into your body.

Anti-nausea medicine. If you are throwing up a lot and cannot keep any fluids down, a doctor may give you medicine to help stop the vomiting. This can help you drink more.

Antibiotics. Antibiotics only work against bacteria. They do not work against viruses. Since most stomach flu is caused by viruses, antibiotics usually do not help. A doctor will only give you antibiotics if tests show that bacteria caused your illness.

Medicine to stop diarrhea. These medicines are generally not recommended, especially for children. They can actually make things worse in some cases. Talk to a doctor before using them.