What to know about vomiting

By Caitlin Geng

Vomiting is the body’s way of expelling harmful substances. It is not necessarily a sign of a serious problem, and it usually only lasts a day or two.

There are many potential causes of vomiting. Some common causes are food poisoning, morning sickness in pregnancy, motion sickness, and gastroenteritis.

However, vomiting is sometimes a symptom of more serious problems.

It could indicate an issue, such as appendicitis, which requires medical attention. If an individual is vomiting for more than 24 hours, has blood in their vomit, or thinks they may have ingested poison, they should contact a doctor.

Read more to learn about the causes of vomiting, how to treat it, how to prevent it, and more.

Causes of vomiting

There are a variety of potential common causes of vomiting, which include the below.

Gastroenteritis

Commonly called stomach flu, gastroenteritis is an inflammation of the intestines. It is usually due to a virus, bacteria, or parasite resulting from ingesting contaminated food or water.

Symptoms of gastroenteritis include vomiting, diarrhea, headache, fever, and stomach pain.

Morning sickness

Also known as nausea and vomiting of pregnancy, morning sickness affects up to 80% of people during pregnancy. It can cause vomiting at any time of day, despite its name.

For many people, nausea and vomiting is an early sign of pregnancy. It usually resolves on its own.

Motion sickness

Motion sickness makes people feel nauseous and dizzy as they travel. It can also cause vomiting.

In particular, it commonly affects children and pregnant individuals. It occurs when sensory signals from the inner ears, eyes, and muscles do not match. However, people usually feel better once the journey is over.

Bowel obstruction

A person may vomit because their intestines become obstructed. This obstruction blocks food and liquids from passing through the digestive system, and vomiting occurs when food or fluid backs up in the stomach.

Appendicitis

Appendicitis is a condition where the appendix acquires an infection and becomes inflamed. It usually causes severe pain in the lower right-hand side of the abdomen.

In addition to pain, it can also cause nausea, vomiting, fever, diarrhea, or constipation. People with appendicitis symptoms need to seek medical attention.

Pancreatitis

Pancreatitis occurs when the pancreas becomes inflamed, which usually causes a sudden onset of pain in the upper mid-left abdomen, below the breastbone.

Individuals may also have nausea, vomiting, diarrhea, lack of appetite, fever, and rapid pulse. Those with pancreatitis symptoms need to seek medical help.

Brain and central nervous system disorders

Some disorders of the brain or central nervous system activate the vomiting center of the brain.

These include infections, such as meningitis or encephalitis and migraine headaches. Conditions that cause elevated pressure inside the skull, including head injuries, brain hemorrhages, and tumors, can also cause vomiting.

Ingesting toxins or drugs

Ingesting toxins, such as those in lead and certain plants and food, can cause severe nausea and vomiting.

Various drugs can cause vomiting, :

antibiotics
chemotherapy drugs
opioids, such as morphine
cannabis (marijuana)

People who have, or think they may have, ingested a toxin or chemical should seek medical attention.

Cyclic vomiting syndrome

Cyclic vomiting syndrome is a rare disorder that can cause people to vomit at varying intervals. This condition usually begins during childhood and can persist into adulthood.

Adults who develop cyclic vomiting syndrome may develop the disorder due to chronic marijuana use.

Psychological causes

Stress and anxiety may cause people to experience nausea and vomiting. Other people may induce vomiting, such as people with bulimia nervosa.

Vomiting-relieving medication

There are a variety of medications to treat vomiting — doctors often refer to them as antiemetics.

Some antiemetics work by blocking signals from reaching the vomiting center of the brain, while others speed up the movement of food through the gut.

Some common medications for vomiting include the below.

Dopamine-blocking medications

These include prochlorperazine, haloperidol, chlorpromazine, perphenazine, promethazine, and levomepromazine. They work by blocking activity in a chemical in the brain called dopamine.

They may be effective against vomiting due to some cancers and cancer treatments. People can also use them to treat nausea that opiate medications may induce.

Antihistamines

Some antihistamine medications include promethazine, cyclizine, and cinnarizine. Experts believe they work by blocking receptors for histamine in the area of the brain that causes nausea and vomiting. People use these medications to treat vomiting from various causes.

Hyoscine

This medicine works by blocking the activity of a chemical in the brain called acetylcholine. People often use it to treat nausea due to motion sickness or inner ear problems.

Serotonin-blocking medications

Some serotonin-blocking medications include palonosetron, granisetron, and ondansetron. These medications block serotonin activity in the brain and gut, which could cause nausea and vomiting.

Individuals experiencing vomiting due to chemotherapy may use these medications.

Metoclopramide

This medicine works directly on the gut. It reduces feelings by stimulating gastrointestinal movement, helping the stomach empty itself, and moving food through the gut more quickly. It also blocks dopamine receptors in the brain.

People often use this medication if they are vomiting due to slow gut problems or migraine.

Other vomiting treatments

Besides taking medication to treat vomiting, a person can try: