Norovirus and the winter vomiting bug: when to manage at home and when to call a GP
Every autumn the same bug sweeps through London households, offices and nurseries: one person starts vomiting, and within days the whole family is down. Norovirus, the winter vomiting bug, is the most common stomach bug in the UK, and most cases need nothing more than fluids, rest and time. But some cases do need a doctor, and knowing the difference matters, especially with babies, older relatives and anyone whose health is already fragile. At The Online GP by The Wellness, our doctors assess stomach bugs by video or phone every day, and most patients tell us the reassurance alone was worth the call.
Key points
Norovirus causes sudden vomiting and diarrhoea, often with cramps, aching and a mild fever. It usually passes in two to three days.
It spreads extremely easily and you are contagious from the first symptoms until at least 48 hours after they stop.
Most healthy adults recover with fluids, oral rehydration salts and rest. Antibiotics do not help; it is a virus.
See a GP urgently if there are signs of dehydration, blood in the vomit or stool, a high fever, or symptoms lasting beyond three days.
Babies, older people, pregnant women and anyone immunocompromised should be assessed sooner rather than later.
A phone consultation at The Online GP by The Wellness costs £59 for 15 minutes, with video at £150 and in-person at £220.
What norovirus actually is
Norovirus is a highly contagious virus that inflames the stomach and intestines. It typically arrives suddenly: nausea, vomiting, watery diarrhoea, stomach cramps, sometimes aching limbs, headache and a mild temperature. Symptoms start 12 to 48 hours after exposure and usually last two to three days. It is unpleasant but short, and in a healthy adult it very rarely causes lasting harm. The main danger is dehydration, which is what we watch for, and that danger concentrates in the very young, the very old and the chronically unwell.
Why it spreads through whole households
Very few virus particles are enough to infect, and they survive on surfaces for days. You catch it from an infected person, contaminated food or water, or by touching a surface and then your mouth. You are infectious from the moment symptoms start until at least 48 hours after they finish, which is why the whole family so often follows the first case. Soap and water beats alcohol gel against norovirus, bleach-based cleaning beats a quick wipe, and the 48-hour rule for staying off work, school and nursery genuinely protects everyone else.
Looking after yourself at home
The treatment is fluid replacement. Small, frequent sips of water or oral rehydration solution, little and often through the vomiting phase, then light food as appetite returns. Oral rehydration salts from any pharmacy replace the salts diarrhoea strips out, and they matter most for children and older people. Rest, paracetamol for fever and aches, and patience do the rest. Avoid anti-diarrhoea tablets for children, and use them cautiously yourself: slowing the gut down is not always helpful when the body is clearing a virus. Anti-sickness medication can help adults keep fluids down, and that is one of the things a GP can prescribe when vomiting will not settle.
When a pharmacy is enough, and when you need a GP
For a healthy adult with classic symptoms, fluids and time are enough. Call a GP the same day if you cannot keep even sips of fluid down, if you pass little or dark urine, feel dizzy on standing, or have a dry mouth and sunken eyes, because those are dehydration warning signs. Blood in vomit or stool, severe or localising abdominal pain, a fever above 39C, confusion, or symptoms stretching past three days all need medical assessment. And for babies, toddlers, frail older relatives, pregnant women and anyone on chemotherapy or immune-suppressing medicines, do not wait for red flags: get advice early. Our doctors can assess hydration by video, prescribe anti-sickness treatment where appropriate, arrange tests if something does not fit, and issue a fit note if you need one.
Protecting the rest of the family
Once norovirus is in the house, the goal is containment. The ill person uses their own towel and, if possible, their own bathroom. Wash hands with soap and water after the toilet and before preparing food, clean toilets, taps and door handles with a bleach-based product, wash soiled bedding and clothing hot and separately, and do not prepare food for others while symptomatic or for 48 hours after. Children stay off school or nursery for 48 hours after symptoms stop, and adults off work, especially in food handling, healthcare and care work.
What it costs
Some London clinics charge £100 to £250 for a walk-in appointment about a stomach bug. At The Online GP by The Wellness, a phone consultation is £59 for 15 minutes, a video consultation is £150, and an in-person appointment at our Marylebone clinic is £220. Most stomach bug questions are sorted comfortably by phone, prescriptions go straight to your nominated pharmacy, and fit notes arrive the same day.
Why people choose The Online GP by The Wellness
Every consultation is with a GMC-registered doctor, and you can usually be seen the same day, often within hours. There is no waiting room to spread your bug around, no week-long wait for an NHS slot, and no guesswork about whether your case is the simple kind or the kind that needs acting on. That judgment, quickly and calmly delivered, is what our patients come back for.
Worried about a stomach bug that is not settling? Call 020 3951 3429, message us on WhatsApp, or book a same-day consultation.
Frequently asked questions
How long does norovirus last?
Symptoms usually last two to three days. Vomiting tends to settle first, with diarrhoea trailing a day or so behind. If you are still significantly unwell after three days, or getting worse rather than better, speak to a GP.
When am I no longer contagious?
You are most contagious while symptomatic and for the first 48 hours after symptoms stop, though the virus can linger a little longer. Stay off work, school and nursery for at least 48 hours after your last symptoms, and keep up strict hand hygiene for several days more.
Can a GP prescribe anything for norovirus?
There is no cure; antibiotics do not touch it. What a GP can do is assess whether you are dehydrated, prescribe anti-sickness medication so fluids stay down, rule out other causes when the picture does not fit, and advise on when hospital assessment would be needed. That assessment is often what turns a worrying week into a manageable one.
Should my child stay off school?
Yes, for 48 hours after their last episode of vomiting or diarrhoea. Schools and nurseries ask for this because norovirus rips through classrooms, and sending a child back early is how whole year groups go down.
Is it food poisoning or norovirus?
It is hard to tell, and often it does not matter: both are managed the same way. Food poisoning tends to follow a suspect meal within hours to a couple of days and affects people who shared it; norovirus spreads person to person through a household. A GP can help you work out which is more likely and whether anything needs reporting or testing.
How much does a consultation cost at The Online GP?
A phone consultation is £59 for 15 minutes, a video consultation is £150, and an in-person appointment is £220. Prescriptions and fit notes are included, sent the same day.
References
Norovirus: symptoms, transmission and the 48-hour rule. UK Health Security Agency guidance. 2025.
Oral rehydration therapy in acute gastroenteritis. NICE Clinical Knowledge Summaries. 2024.
This article is for information and does not replace personal medical advice. All consultations at The Online GP by The Wellness are with GMC-registered doctors. Written by The Wellness Team and medically reviewed by The Wellness Clinical Team. Last updated October 2026.