Nausea — causes and treatment
Reviewed by the My London Pharmacy clinical team, Yvonne Lim, Pharmacist Independent Prescriber
·29 July 2026
·8 min read
Quick answer
Nausea is the unpleasant feeling of needing to be sick, and it has many possible causes, from infections and motion to medicines and migraine. Most short-lived nausea settles with rest, fluids and simple self-care, while persistent or severe nausea may need assessment and targeted anti-sickness treatment.
What nausea is
Nausea is the uncomfortable sensation that you might vomit, often felt in the upper stomach, chest or throat and sometimes accompanied by sweating, a rush of saliva, dizziness or a loss of appetite. It is a symptom rather than a condition in its own right, and it is one of the body's ways of responding to a wide range of triggers, from something you have eaten to how you are feeling. Vomiting may or may not follow, and the feeling can range from mild queasiness to something quite overwhelming.
Because nausea can arise from so many different sources, the most helpful approach is to consider what else is going on at the same time. Are you feverish, in pain, pregnant, travelling, or taking a new medicine? Short-lived nausea is usually nothing to worry about and settles on its own, but understanding the likely cause guides both self-care and, where needed, treatment. It also helps you judge when the feeling is a passing nuisance and when it is a sign that you should seek advice.
Common causes
There are many everyday reasons for feeling sick, and identifying the likely cause helps you respond appropriately rather than worrying unnecessarily. Nausea is extremely common and, most of the time, has a straightforward explanation.
- Viral tummy bugs and food poisoning, often alongside diarrhoea and stomach cramps.
- Motion sickness from travel by car, boat, train or plane.
- Pregnancy, particularly in the early weeks, when nausea is very common.
- Migraine, which frequently causes nausea alongside headache and sensitivity to light.
- Some medicines, especially when first started, or drinking too much alcohol.
- Anxiety and stress, pain, low blood sugar, or strong smells and tastes.
Less commonly, nausea can point to a problem needing assessment, such as an infection elsewhere in the body, a digestive condition, inner-ear disturbance, or a reaction to treatment. This is why nausea that is persistent, severe or comes with other worrying symptoms is always worth reviewing rather than simply enduring.
Self-care that helps
For most short-lived nausea, simple measures ease symptoms while your body recovers, and there is often no need for medication. Small, practical steps tend to work better than forcing yourself back to normal too quickly or eating a large meal before you feel ready.
- Sip clear fluids regularly to stay hydrated, especially if you have been sick or have diarrhoea.
- Eat small, plain meals such as toast, crackers or plain rice rather than large, rich or greasy ones.
- Get plenty of rest, sit upright after eating, and let some fresh air into the room.
- Avoid strong smells, cooking odours and anything that makes the feeling worse.
- Ginger, in tea or biscuits, and slow, deep breathing help some people.
- For motion sickness, look at the horizon, sit where movement is felt least, and avoid reading while travelling.
Staying hydrated is the priority, particularly for young children and older adults, who can become unwell more quickly if fluids are lost. Rehydration sachets can help replace salts if you have been sick repeatedly.
Anti-sickness treatment options
When nausea is persistent, distressing or interfering with your ability to eat and drink, anti-sickness medicines, known as antiemetics, may help, and a clinician can advise which is appropriate for the underlying cause. Different medicines suit different situations, because the pathways that trigger nausea vary depending on whether it comes from the inner ear, the stomach, a migraine or a medicine, so the choice is matched to why you feel sick and to your wider health.
For suitable people, options such as Prochlorperazine, which is often used for nausea linked to inner-ear problems and some other causes, or Ondansetron 8mg Tablets may be considered. These treatments are chosen for the specific situation and your circumstances rather than used routinely for every bout of queasiness, and they should be taken on clinical advice, as they have their own cautions and possible side effects. Importantly, if nausea is due to a specific condition, treating that underlying cause is a central part of settling the symptom, so anti-sickness medicines are usually one part of a broader plan.
How anti-sickness medicines are matched to the cause
One reason it is worth understanding what is behind your nausea is that anti-sickness medicines are not interchangeable. The signals that make you feel sick can start in different places, the inner ear and balance system, the gut, the brain's response to certain medicines, or the migraine pathways, and different antiemetics act on different parts of that network. A medicine that works well for travel or inner-ear nausea may be less suited to nausea from another source, which is why a clinician tailors the choice.
This is also why self-selecting a medicine is not always the best route. A short conversation about your symptoms, their likely cause, your other medicines and your general health allows the most appropriate option to be chosen and the right dose and timing to be advised. Where the nausea is a side effect of something you take, adjusting that treatment may resolve the problem without needing to add another medicine at all.
Nausea in specific situations
Some causes of nausea deserve a particular mention because they are so common or need a tailored approach. Nausea and vomiting in early pregnancy affect many people and usually ease as pregnancy progresses, but if they are severe, stopping you keeping food or fluids down, it is important to seek advice, as help is available and dehydration needs to be avoided. Treatments used in pregnancy are chosen carefully with a clinician.
Nausea linked to migraine often improves as the headache is treated, while travel-related nausea can frequently be prevented with planning and, where appropriate, remedies taken before a journey. Nausea that appears after starting a new medicine is worth mentioning to your prescriber, as the dose or timing can sometimes be adjusted. In each of these situations, understanding the cause allows the most suitable and safest approach to be chosen, rather than treating the nausea in isolation.
When nausea keeps coming back
Most nausea is short-lived, but some people experience it on and off over weeks or longer. Recurring nausea can be linked to ongoing conditions such as acid reflux or other digestive problems, inner-ear conditions that affect balance, recurring migraine, or anxiety, and it can also be a side effect of a regular medicine. Because the pattern and the accompanying symptoms differ in each case, an assessment is the most reliable way to get to the bottom of it.
If a particular medicine seems to be the trigger, it is worth raising with the prescriber rather than stopping it yourself, as the dose, timing or choice can sometimes be adjusted. Where an underlying condition is found, treating that is usually the key to settling the nausea, with anti-sickness medicines used as one supporting part of the plan rather than the whole answer.
Nausea in children and older adults
Nausea and vomiting deserve extra care in young children, older adults and anyone with other health conditions, because they can become dehydrated more quickly. The priority is steady fluid replacement in small, frequent sips, and rehydration sachets can help replace lost salts. Rich, greasy or very sugary foods are best avoided until the stomach has settled, with a return to normal eating as the appetite comes back.
Watch for signs that fluids are not being kept up, such as passing little urine, a dry mouth, unusual drowsiness or dizziness, as these warrant advice sooner rather than later. In babies and very young children in particular, it is better to seek advice early than to wait, because they can become unwell faster than adults.
When to seek clinical help
See a clinician if nausea lasts more than a couple of days, keeps returning, or is severe enough to stop you keeping fluids down. Signs of dehydration, such as passing little urine, a very dry mouth, dizziness, sunken eyes or feeling very tired and weak, also warrant advice, particularly in children, older adults and anyone with other health conditions who can become unwell more quickly.
Seek urgent help if nausea comes with a severe headache, a stiff neck and dislike of bright light, chest pain, a very high temperature, severe or worsening tummy pain, or blood in your vomit, or if it follows a recent head injury. These combinations can point to something that needs prompt assessment. For ongoing or unexplained nausea, a planned consultation helps find the cause, check nothing more serious is behind it, and choose the right treatment so you feel better and stay well.
Frequently asked questions
What is the most common cause of nausea?
Everyday causes include tummy bugs, food poisoning, motion sickness, early pregnancy, migraine, some medicines and alcohol. Most short-lived nausea settles with rest and fluids.
How can I ease nausea at home?
Sip clear fluids, eat small plain meals, rest, get fresh air and avoid strong smells. Ginger and slow breathing help some people, and staying hydrated is the priority.
Are there medicines for nausea?
Yes. Anti-sickness medicines such as Prochlorperazine or Ondansetron 8mg Tablets may be considered for suitable people, matched to the cause. They are best used on clinical advice.
Is nausea in pregnancy normal?
Nausea is very common in early pregnancy and usually eases over time. If it is severe or stops you keeping fluids down, seek advice, as help and suitable treatment are available.
When is nausea a sign of something serious?
Seek urgent help if nausea comes with a severe headache, stiff neck, chest pain, severe tummy pain, a very high temperature, blood in vomit, or after a head injury.
How long should nausea last?
Short-lived nausea often settles within a day or two. See a clinician if it persists, keeps returning, or stops you keeping fluids down, as this may need assessment.