Nausea: Common Causes, What Helps and When to Get Medical Advice

Nausea is the unpleasant feeling that you might be sick. Some people describe it as feeling queasy, unsettled, carsick, seasick, sick to the stomach, or as if food is sitting heavily in the stomach. Nausea may happen on its own, or it may come with vomiting, diarrhoea, dizziness, headache, abdominal pain, fever, heartburn, anxiety or pregnancy symptoms.

Most nausea is short-lived and improves with simple self-care, such as resting, sipping fluids and eating small amounts of plain food. But nausea can also be caused by many different things, from food poisoning and migraine to medicines, reflux, pregnancy, anxiety, dehydration, low blood sugar, inner ear problems and more serious conditions.

This guide explains common causes of nausea, what may help at home, when to ask a pharmacist, when to contact a GP or NHS 111, and when nausea needs urgent medical help.

What is nausea?

Nausea is the sensation of feeling sick, even if you do not actually vomit. It can feel mild and temporary, or intense and overwhelming. Some people feel nausea in the stomach. Others feel it in the throat, chest, head or whole body.

Nausea is not a diagnosis by itself. It is a symptom. The cause may be something simple, such as eating too much rich food, motion sickness or a short stomach bug. But if nausea is persistent, recurring, severe or linked with other symptoms, it may need medical assessment.

The NHS advises seeing a GP if you are feeling sick and do not feel better in a few days, or if nausea often keeps coming back. You can read official NHS advice on feeling sick or nausea.

Common causes of nausea

Nausea has many possible causes. The most likely explanation often depends on what else is happening at the same time.

Common causes include:

• food poisoning
• norovirus or another stomach bug
• indigestion or acid reflux
• migraine
• motion sickness
• pregnancy
• anxiety or panic
• dehydration
• low blood sugar
• alcohol
• medicines or supplements
• ear or balance problems
• gallbladder problems
• urinary infections
• pain
• heat exhaustion
• less commonly, heart, brain, liver, kidney or bowel problems

If nausea comes with vomiting or diarrhoea, see Diarrhoea and Vomiting in Adults. If abdominal pain is a major symptom, see Abdominal Pain: Common Causes by Location and When to Get Help.

Nausea with vomiting or diarrhoea

Nausea with vomiting or diarrhoea is often caused by a stomach bug, food poisoning, norovirus or gastroenteritis. It may come on suddenly and can make you feel very unwell for a short time.

Symptoms may include:

• feeling sick
• vomiting
• watery diarrhoea
• stomach cramps
• fever or chills
• headache
• loss of appetite
• tiredness or weakness

The main risk is dehydration, especially if you are vomiting repeatedly or have frequent diarrhoea. Take small sips of fluid often, and consider oral rehydration sachets from a pharmacy if you are losing a lot of fluid.

Related guides include Food Poisoning: Symptoms, How Long It Lasts and When to Get Help, What Is Norovirus? and Dehydration Symptoms in Adults and Children.

Nausea after eating

Nausea after eating can happen for many reasons. Sometimes it is caused by eating too quickly, eating a large meal, rich food, alcohol, anxiety or indigestion. If it keeps happening, other causes may need to be considered.

Possible causes include:

• acid reflux or heartburn
• indigestion
• food poisoning
• gallstones or gallbladder pain
• stomach ulcers
• IBS
• food intolerance
• pregnancy
• gastroparesis, where the stomach empties slowly
• anxiety around eating

Seek medical advice if nausea after eating is persistent, linked with weight loss, vomiting, blood in vomit, black stools, difficulty swallowing, severe pain, jaundice, or you are avoiding food because of symptoms.

For related information, see Heartburn, Acid Reflux and GORD, Gallstones: Symptoms, Gallbladder Pain and When Surgery Is Needed and Stomach Ulcers: Causes, Symptoms, H. pylori and Treatment.

Nausea with stomach pain

Nausea with stomach pain can be caused by indigestion, trapped wind, food poisoning, constipation, IBS, gallstones, stomach ulcers, urinary infections, kidney stones, appendicitis or other abdominal conditions.

Mild stomach cramps with diarrhoea often point towards a stomach bug or food poisoning. Pain after fatty meals may suggest gallbladder problems. Burning pain with acid taste or burping may suggest reflux. Lower abdominal pain with urinary symptoms may suggest a urine infection.

Seek urgent advice if abdominal pain is:

• severe
• sudden
• worsening
• focused in one area
• associated with a rigid or swollen abdomen
• linked with repeated vomiting
• linked with blood in stool or black stool
• associated with fainting, confusion or severe weakness

See Abdominal Pain: Common Causes by Location for a fuller guide.

Nausea with fever

Nausea with fever may happen with infections such as flu, COVID-like illness, food poisoning, norovirus, urinary infection, kidney infection, pneumonia or other inflammatory conditions.

Fever with nausea needs more caution if it is high, persistent or associated with severe symptoms.

Get medical advice if nausea and fever come with:

• severe abdominal pain
• stiff neck
• severe headache
• confusion or drowsiness
• rash that does not fade when pressed
• shortness of breath
• chest pain
• pain when urinating
• back or side pain
• signs of dehydration

For more detail, read Fever in Adults: What Temperature Means and When to Worry.

Nausea with dizziness

Nausea and dizziness often happen together. This may be due to motion sickness, vertigo, dehydration, low blood sugar, anxiety, migraine, low blood pressure, inner ear problems or side effects of medicines.

Common patterns include:

• Spinning sensation: may suggest vertigo or an inner ear problem.
• Lightheadedness on standing: may suggest dehydration, low blood pressure or not eating enough.
• Dizziness with headache or visual symptoms: may suggest migraine, but stroke must be considered if symptoms are sudden or unusual.
• Dizziness with palpitations: may need assessment for heart rhythm or anxiety causes.

Seek urgent help if dizziness with nausea comes with weakness, speech problems, sudden vision loss, severe headache, chest pain, fainting, severe shortness of breath or difficulty walking.

Related guides include Dizziness: Common Causes and When to Worry, Fainting and Blackouts: Causes, Tests and When to Call 999 and Heart Palpitations: Causes and When to See a Doctor.

Nausea and migraine

Nausea is a common migraine symptom. Some people vomit during migraine attacks. Nausea may come with throbbing head pain, light sensitivity, sound sensitivity, visual aura, dizziness, tiredness or needing to lie still in a dark room.

Migraine nausea may improve when the migraine improves, but repeated vomiting can make it difficult to keep painkillers down. A GP or pharmacist may be able to advise on suitable treatment options.

Seek urgent help if the headache is sudden and severe, different from your usual headaches, linked with weakness, confusion, seizure, fever, stiff neck, vision loss or head injury.

Read more in Migraine: Symptoms, Triggers and Treatment Options in the UK and Headache: Causes, Red Flags and When to Seek Urgent Help.

Nausea and acid reflux

Acid reflux can cause nausea, especially after meals or when lying down. It happens when stomach acid travels back up towards the throat.

Symptoms may include:

• heartburn
• acid taste in the mouth
• burping
• nausea after eating
• cough or throat clearing
• hoarse voice
• feeling of food coming back up

What may help:

• eating smaller meals
• avoiding lying down soon after eating
• reducing fatty or spicy foods if they trigger symptoms
• limiting alcohol and caffeine if they worsen reflux
• raising the head of the bed if symptoms happen at night
• asking a pharmacist about antacids or reflux medicines

Seek medical advice if reflux symptoms are persistent, severe, new after age 55, linked with difficulty swallowing, vomiting blood, black stools, unexplained weight loss or anaemia.

Nausea in pregnancy

Nausea is common in pregnancy, especially in the first trimester. It is often called morning sickness, although it can happen at any time of day. Some people have mild nausea; others have severe vomiting that needs medical treatment.

Seek medical advice if you are pregnant and:

• you cannot keep fluids down
• you are losing weight
• you are peeing much less than usual
• urine is very dark
• you feel dizzy or faint
• vomiting is severe or persistent
• you have abdominal pain or bleeding
• you have fever
• you are worried

Severe pregnancy sickness, known as hyperemesis gravidarum, can cause dehydration and may need treatment. Do not struggle on if symptoms are severe.

If you have pregnancy-related concerns, contact your midwife, GP, maternity unit or NHS 111 depending on the situation.

Nausea from medicines or supplements

Many medicines and supplements can cause nausea, especially when first started, when the dose is increased, or when taken on an empty stomach.

Common examples include:

• antibiotics
• iron tablets
• painkillers such as anti-inflammatory medicines
• metformin
• some antidepressants
• opioid pain medicines
• some blood pressure medicines
• some weight-loss medicines
• vitamin or mineral supplements

Do not stop prescribed medicine without advice, especially if it is important for a long-term condition. Ask a pharmacist or GP whether the medicine should be taken with food, at a different time of day, or whether an alternative is needed.

If you use weight-loss injections and develop severe or persistent vomiting, severe abdominal pain, dehydration or inability to keep fluids down, seek medical advice. You may also find Weight Loss Injections in the UK and Are Online Weight-Loss Jabs Safe? useful.

Nausea from anxiety or panic

Anxiety can affect the gut. Some people feel sick before stressful events, during panic attacks, or during periods of ongoing worry. Nausea may come with a tight stomach, butterflies, diarrhoea, sweating, trembling, fast heartbeat, chest tightness or feeling unable to relax.

However, do not assume nausea is “just anxiety” if it is new, severe, persistent or linked with red flags such as chest pain, fainting, severe abdominal pain, weight loss, blood in stool, vomiting blood or neurological symptoms.

If anxiety is a recurring issue, see Mental Health Support Options in the UK and How to Access Mental Health Services in the UK.

Nausea from dehydration or heat

Dehydration can cause nausea, dizziness, headache, weakness, dry mouth and dark urine. It may happen after vomiting, diarrhoea, sweating, fever, exercise or hot weather.

Heat exhaustion can also cause nausea, especially during hot weather, after sun exposure, or after physical activity in heat.

Watch for symptoms such as:

• nausea or vomiting
• dizziness
• headache
• heavy sweating
• muscle cramps
• extreme thirst
• weakness
• peeing less often
• confusion or collapse in severe cases

Move somewhere cool, sip fluids, rest and cool the body. Seek urgent help if symptoms are severe or not improving.

Related guides include Dehydration Symptoms in Adults and Children, Heat Exhaustion and Heatstroke and How to Prevent Heat Exhaustion and Heatstroke in Hot Weather.

Nausea from low blood sugar

Low blood sugar can cause nausea, shakiness, sweating, hunger, weakness, dizziness, headache, confusion, anxiety or palpitations. It is more likely in people with diabetes using insulin or certain diabetes medicines, but some people feel sick and shaky when they have not eaten for a long time.

If you have diabetes, follow your sick day rules and your diabetes team’s advice. Seek urgent help if you are confused, drowsy, unable to keep fluids down, have very high or very low blood sugar, ketones, or you are unsure what to do.

For related information, see HbA1c and Blood Sugar Results Explained and Shaky Hands or Feeling Shaky: Common Causes and When to Get Help.

Nausea and alcohol

Alcohol can irritate the stomach, trigger reflux, affect blood sugar, cause dehydration and lead to nausea or vomiting. Hangover-related nausea usually improves with time, fluids, rest and eating when able.

Seek urgent help if vomiting after alcohol comes with:

• confusion
• slow or irregular breathing
• blue, grey or pale skin
• seizure
• collapse
• vomiting blood
• head injury
• the person cannot be woken properly

Repeated nausea linked with alcohol may be a sign to review alcohol intake and liver health. If liver results are relevant, see Liver Function Test Results Explained.

Nausea and heart problems

Nausea can sometimes happen with heart problems, especially if it comes with chest pain, chest pressure, sweating, shortness of breath, pain spreading to the arm, back, neck or jaw, dizziness or feeling faint.

Call 999 if nausea comes with:

• chest pain, pressure, heaviness or tightness
• pain spreading to the arm, back, neck, jaw or shoulder
• shortness of breath
• sweating
• fainting or collapse
• severe weakness
• a sense that something is seriously wrong

Do not drive yourself to hospital if you think it could be a heart attack. Call 999.

For more information, see Chest Pain: When to Worry and Shortness of Breath: Common Causes and When to Call 999.

Motion sickness and travel nausea

Motion sickness happens when the brain receives mixed signals from the eyes, inner ears and body. It can happen in cars, boats, planes, trains, fairground rides or virtual reality.

Symptoms may include:

• nausea
• vomiting
• cold sweats
• dizziness
• headache
• pale skin
• increased saliva

What may help:

• sit where motion is least noticeable
• look at the horizon
• avoid reading or looking down at a phone
• get fresh air if possible
• eat lightly before travel
• avoid alcohol
• ask a pharmacist about travel sickness medicines before the journey

What helps nausea at home?

What helps depends on the cause, but mild nausea often improves with simple measures.

Try:

• sipping water or oral rehydration solution
• eating small, plain meals
• avoiding greasy, spicy or very rich foods
• getting fresh air
• sitting upright after eating
• resting in a quiet room
• avoiding strong smells
• avoiding alcohol
• avoiding large meals
• eating slowly

Some people find ginger, peppermint or dry crackers helpful, although these do not work for everyone and may not suit every medical condition. Ask a pharmacist if you are pregnant, taking medicines, or have a long-term condition.

What should you eat when feeling sick?

If you feel sick, do not force large meals. Small amounts of plain food may be easier.

Foods that may be better tolerated include:

• toast
• crackers
• rice
• bananas
• plain pasta
• potatoes
• soup
• small snacks rather than large meals

Avoid foods that make nausea worse. For some people this includes fried foods, strong smells, spicy food, alcohol, coffee or very sweet drinks.

What should you drink when nauseous?

Small, frequent sips are usually better than drinking a large glass at once. If you have vomited, wait a few minutes and then restart with tiny sips.

Options include:

• water
• oral rehydration solution
• diluted squash
• clear soup or broth
• weak tea if tolerated

If you are vomiting repeatedly or have diarrhoea, oral rehydration sachets from a pharmacy can help replace fluids and salts.

Should you take anti-sickness medicine?

Anti-sickness medicines can help in some situations, such as motion sickness, migraine-related nausea, pregnancy sickness, vertigo or nausea from certain medicines. But the right option depends on the cause.

Do not take someone else’s anti-sickness medicine. Some are not suitable for people with certain heart conditions, Parkinson’s disease, glaucoma, epilepsy, pregnancy, older age or interactions with other medicines.

Ask a pharmacist, GP or prescribing clinician if:

• nausea is severe
• you keep vomiting
• you are pregnant
• you have a long-term condition
• you take regular medicines
• you need travel sickness prevention
• nausea is caused by a medicine

When to see a pharmacist

A pharmacist can help with mild nausea, travel sickness, indigestion, reflux, dehydration risk, medicine side effects and advice on when to seek further help.

Speak to a pharmacist if:

• you feel sick but are otherwise well
• you need advice on oral rehydration sachets
• you have nausea with heartburn or indigestion
• you need travel sickness medicine
• you think a medicine may be causing nausea
• you are not sure whether symptoms need a GP

For more about pharmacy advice, see When to See a Pharmacist Instead of a GP.

When to contact a GP or NHS 111

Contact a GP, out-of-hours service or NHS 111 if:

• nausea does not improve after a few days
• nausea keeps coming back
• you are vomiting repeatedly
• you cannot keep fluids down
• you have signs of dehydration
• you are losing weight without trying
• you have persistent abdominal pain
• you have fever that is high or not settling
• you have blood in your stool or black stool
• you have vomiting after a head injury
• you recently started a new medicine
• you are pregnant and symptoms are difficult to manage
• you have diabetes and are vomiting or unwell
• you are older, frail, immunosuppressed or have a significant long-term condition
• you are worried or unsure what to do

You can use NHS 111 online in England if you need urgent advice and it is not a 999 emergency.

If you need help arranging care, see How to Get a GP Appointment Quickly in the UK.

When to call 999 or go to A&E

Call 999 or seek emergency help if nausea may be part of a serious emergency.

Call 999 if nausea comes with:

• chest pain, pressure, heaviness or pain spreading to the arm, back, neck or jaw
• severe shortness of breath
• collapse or fainting
• sudden weakness, face drooping or speech problems
• sudden severe headache
• confusion or severe drowsiness
• stiff neck with fever or light sensitivity
• vomit that contains blood or looks like coffee grounds
• green vomit in adults
• severe or sudden abdominal pain
• severe dehydration
• seizure
• severe allergic reaction symptoms

Trust your judgement. If someone looks seriously unwell or is deteriorating quickly, seek urgent help.

What tests might be needed?

Most short-lived nausea does not need tests. If nausea is persistent, recurring or linked with other symptoms, a GP may consider tests based on the likely cause.

Possible checks include:

• pregnancy test
• urine test
• blood pressure and pulse
• blood sugar or HbA1c
• full blood count
• liver function tests
• kidney function tests
• thyroid blood tests
• inflammation markers
• stool test if infection is suspected
• abdominal ultrasound
• gastroscopy in selected cases
• ECG if heart symptoms are possible

Related guides include How to Understand Blood Test Results, Urine Test Results Explained, Abdominal Ultrasound: What It Shows, Gastroscopy: When It’s Needed and What It Shows and ECG Results Explained.

How to describe nausea clearly to a clinician

If you speak to a pharmacist, GP or NHS 111, clear details can help them decide what may be causing nausea and how urgent it is.

Useful details include:

• when nausea started
• whether it is constant or comes and goes
• whether you have vomited
• whether you have diarrhoea
• whether you have abdominal pain and where it is
• whether nausea is worse after eating
• whether you have fever
• whether you feel dizzy or faint
• whether you have headache or migraine symptoms
• whether you could be pregnant
• whether you started a new medicine
• whether you have chest pain or shortness of breath
• whether you have lost weight
• whether you can keep fluids down
• how often you are peeing and what colour your urine is

Frequently asked questions about nausea

What is the most common cause of nausea?

Common causes include stomach bugs, food poisoning, indigestion, reflux, pregnancy, migraine, motion sickness, anxiety, medicines, dehydration and alcohol. The cause is more likely to be clear when you look at other symptoms such as vomiting, diarrhoea, fever, dizziness or pain.

How long should nausea last?

Mild nausea may settle within hours or a couple of days depending on the cause. See a GP if nausea does not improve after a few days or keeps coming back. Seek urgent help sooner if there are red flag symptoms.

What helps nausea quickly?

Small sips of fluid, fresh air, rest, avoiding strong smells, eating small amounts of plain food, and sitting upright may help. If nausea is caused by reflux, migraine, travel sickness or pregnancy, specific treatments may be needed.

Should I make myself vomit if I feel sick?

No. Do not try to make yourself vomit. It can irritate the throat, increase dehydration risk and may be dangerous depending on the cause. Focus on fluids, rest and getting advice if symptoms are severe or persistent.

Can anxiety cause nausea?

Yes. Anxiety can affect the gut and cause nausea, butterflies, diarrhoea, appetite changes and stomach tightness. However, persistent or severe nausea should not automatically be blamed on anxiety, especially with red flag symptoms.

Can dehydration cause nausea?

Yes. Dehydration can cause nausea, dizziness, headache, weakness, dry mouth and dark urine. It can also happen because vomiting or diarrhoea causes fluid loss. Seek advice if you cannot keep fluids down or are peeing much less than usual.

Can nausea be a sign of a heart attack?

Sometimes. Nausea can occur with heart problems, especially if it comes with chest pain, chest pressure, sweating, shortness of breath, fainting or pain spreading to the arm, back, neck or jaw. Call 999 if these symptoms occur.

Why do I feel sick after eating?

Nausea after eating may be caused by indigestion, reflux, rich foods, food poisoning, gallbladder problems, stomach ulcers, IBS, pregnancy, anxiety or medicines. Seek advice if it is persistent, severe, linked with weight loss, vomiting blood, black stools or difficulty swallowing.

Can migraine cause nausea?

Yes. Nausea and vomiting are common during migraine attacks. Migraine may also cause light sensitivity, sound sensitivity, visual aura and dizziness. New or unusual neurological symptoms should be assessed urgently.

What should I drink if I feel sick?

Try small, frequent sips of water or oral rehydration solution. Diluted squash, clear soup or weak tea may also be tolerated. If you vomit, wait a few minutes and restart with tiny sips.

When should I call NHS 111 for nausea?

Use NHS 111 if nausea is severe, you cannot keep fluids down, you have signs of dehydration, symptoms are not improving, you are pregnant and struggling, you have a long-term condition, or you are unsure what to do.

When should nausea be treated as an emergency?

Call 999 if nausea comes with chest pain, severe breathlessness, collapse, stroke symptoms, severe sudden headache, confusion, stiff neck, blood in vomit, green vomit in adults, severe abdominal pain, seizure or severe dehydration.

Final thoughts

Nausea is common and often settles with rest, fluids and simple self-care. It may be caused by food poisoning, a stomach bug, reflux, migraine, pregnancy, anxiety, motion sickness, dehydration, medicines, alcohol or many other causes.

The key is to look at the full pattern. Nausea with diarrhoea and vomiting often points to an infection or food poisoning. Nausea with headache may suggest migraine. Nausea after meals may suggest reflux or gallbladder problems. Nausea with chest pain, severe abdominal pain, confusion, stroke symptoms or dehydration can be urgent.

For official guidance, see NHS advice on feeling sick or nausea, NHS guidance on diarrhoea and vomiting, and NHS 111 online for urgent symptom advice.

This article is for general information only and should not replace medical advice. If you are worried about nausea, vomiting or other symptoms, contact NHS 111, your GP, a pharmacist, or call 999 in an emergency.