Flu is not the same as the common cold. It is caused by a different group of viruses and the symptoms tend to start more suddenly, be more severe and last longer.
The main symptoms of flu are:
You may also have a blocked or runny nose, sneezing and a sore throat, but these tend to be less severe than your other symptoms.
If you're otherwise fit and healthy, there is usually no need to see a doctor for cold or flu-like symptoms.
The best remedy for both colds and flu is to rest at home, keep warm and drink plenty of water to avoid dehydration.
You can take paracetamol or ibuprofen, to lower a high temperature and relieve aches.
Antibiotics are not prescribed for colds or flu as they have no effect on viruses.
Flu can be more serious in those over 65, people with breathing problems or other health conditions such as diabetes or kidney disease, and people with a weakened immune system. Call 111 if you are concerned.
If your symptoms are getting worse over time or haven't improved after a week, call 111 or make an appointment to see your GP.
Your GP practice will offer you a free flu jab in the autumn if you are over 65 or at risk of complications from flu.
Find out more about colds and flu.
You can call 111 for advice if you need urgent medical help and are not sure what to do.
Call 111 when you need medical help fast but it's not a 999 emergency. NHS 111 is available 24 hours a day, 365 days a year. Calls are free from landlines and mobile phones.
If the illness or injury is life-threatening, don't hesitate. Call 999 straight away.