Nausea and vomiting – adults

Nausea is the feeling that you may vomit. Vomiting is the forceful emptying of stomach contents through the mouth. You can have nausea without vomiting, and vomiting does not always relieve nausea.

These are symptoms rather than a disease. Common causes include a stomach infection, food poisoning, migraine, motion sickness, pregnancy and medication side effects. Less often, nausea and vomiting can be linked to a problem that needs urgent treatment.

Short episodes can often be managed at home if you can drink enough and do not have warning signs. The main immediate concern is dehydration, which means your body is losing more fluid than it takes in.

Nausea may feel like queasiness, churning or discomfort in the upper abdomen. You may lose your appetite or notice extra saliva, sweating, dizziness or a strong urge to vomit.

Retching, sometimes called dry heaving, is the movement of vomiting without bringing much up. Repeated vomiting may leave your throat sore and your abdominal muscles tender.

The appearance of vomit can offer clues. Recently eaten food or clear fluid is common. Blood may look bright red or like dark coffee grounds. Green vomit may contain bile, a digestive fluid. Blood, coffee-ground material or repeated green vomit requires urgent medical assessment.

Other symptoms matter. Diarrhoea and cramps often occur with a gut infection. Headache and sensitivity to light may suggest migraine. Severe or worsening pain, fever, confusion, chest discomfort or a swollen abdomen need closer attention.

Common causes include viral gastroenteritis, often called a stomach bug, and food poisoning. These may also cause diarrhoea, cramps and a mild fever.

Alcohol, overeating and some medicines can irritate the stomach or affect the brain pathways that control nausea. Medicines linked with nausea include some antibiotics like amoxicillin or doxycycline, strong pain medicines and cancer treatments. Do not stop a prescribed medicine suddenly; ask a pharmacist or clinician for advice.

Motion sickness and migraine can cause nausea with or without vomiting. Pregnancy is another common cause in people who could be pregnant, especially during early pregnancy.

Less common causes include acid reflux, gallbladder disease and gastroparesis, in which the stomach empties more slowly than usual. Kidney or liver problems, inner-ear disorders and anxiety can also contribute.

Potentially urgent causes include appendicitis, inflammation of the pancreas, a blocked bowel, diabetic ketoacidosis, meningitis, poisoning and some heart problems. These usually cause other warning signs as well as nausea or vomiting.

Call emergency services if nausea or vomiting occurs with:

• Chest pain, pressure, severe breathlessness or fainting
• A sudden severe headache, confusion, stiff neck or new weakness
• Severe or rapidly worsening abdominal pain
• Vomit containing blood or material resembling coffee grounds
• Suspected poisoning or vomiting after a significant head injury

Seek same-day medical care if you cannot keep fluids down and have signs of dehydration. These include passing very little urine, dark urine, a very dry mouth, marked dizziness, unusual sleepiness or weakness.

Repeated green vomit, a swollen abdomen, severe pain or being unable to pass stool or gas also needs prompt assessment. Contact a clinician urgently if you have diabetes and are vomiting, particularly if your blood glucose or ketone levels are high.

Pregnant people should seek prompt advice if vomiting prevents drinking, causes reduced urination or is accompanied by pain or bleeding.

Book a routine appointment if symptoms continue beyond about two days, repeatedly return, cause unplanned weight loss or regularly interfere with eating. Arrange earlier advice if you have a weakened immune system or a serious long-term condition.

A clinician may ask when the symptoms began, how often you vomit and whether you have pain, diarrhoea, fever, headache or dizziness. They may ask about recent meals, travel, alcohol, cannabis, medicines and contact with anyone who has similar symptoms.

Tell them about the appearance of the vomit and whether you can keep fluids down. If pregnancy is possible, that information can affect which tests and treatments are suitable.

An examination may check hydration, temperature, heart rate and the abdomen. Depending on the symptoms, tests may include blood or urine tests, a pregnancy test, an electrocardiogram to assess the heart, or imaging such as an ultrasound or CT scan. Many short, mild episodes do not require testing.

Treatment depends on the cause and whether you are dehydrated. For a mild episode:

• Take frequent small sips of water or oral rehydration solution
• Increase the amount slowly if fluids stay down
• Eat small amounts when you feel ready
• Choose simple foods and avoid rich, fatty meals at first
• Avoid alcohol and rest until you are recovering

Oral rehydration solutions contain a measured balance of water, salts and sugar. They may replace lost fluid more effectively than plain water when vomiting is frequent or accompanied by diarrhoea.

A pharmacist or clinician may recommend an anti-sickness medicine, also called an antiemetic. The best choice depends on the cause, your other medicines, pregnancy and your medical history. Do not take someone else’s medicine or combine products without checking.

If an infection may be responsible, wash your hands with soap and water and avoid preparing food for other people while unwell. Follow local advice about returning to work after vomiting or diarrhoea.

Severe dehydration may require fluids given through a vein. Treatment may also target an underlying problem, such as migraine, a medicine side effect or a bowel condition.

Vomiting caused by a short-lived stomach infection or food-related illness often improves within one or two days. Nausea may take a little longer to settle, and appetite can return gradually.

Recovery time is different when symptoms are caused by migraine, pregnancy, medication or an ongoing digestive condition. Symptoms that persist, worsen or keep returning should be assessed rather than repeatedly managed at home.

Should I make myself eat?

No. Fluids are the first priority. When you feel able, restart food in small amounts. There is usually no need to follow a highly restricted diet once your appetite returns.

Is vomiting without diarrhoea still a stomach bug?

It can be, especially early in the illness, but many other conditions cause vomiting without diarrhoea. Associated symptoms and how long the vomiting lasts help narrow down the cause.

Can stress cause nausea?

Yes. Stress and anxiety can affect the digestive system and trigger nausea. However, new or persistent symptoms should not automatically be assumed to be caused by stress.

Why do I feel worse after drinking quickly?

A large amount of fluid can stretch an irritated stomach and trigger more vomiting. Small, frequent sips are often easier to tolerate.

Is yellow or green vomit always dangerous?

Not always. Bile can appear after the stomach has emptied. However, repeated green vomiting, especially with severe pain, swelling or inability to pass stool or gas, needs urgent assessment.