Headaches can be very painful, but they mostly go away by themselves, and aren’t a sign of something more serious, according to the NHS.
The condition can last from 30 minutes to several hours.
Some headaches may be a sign of a more serious condition, including sleep apnoea or carbon monoxide poisoning.
But, what causes the headaches, and how can you prevent them from coming back?
“Many people call every headache they get a ‘migraine’ but this is unfair to those who get actual migraines,” said London Doctors Clinic GP, Dr Seth Rankin.
“Migraines are a specific type of headache thought to be caused by temporary changes in the chemicals, nerves and blood vessels in the brain.
“There are specific triggers to avoid and also a number of effective treatments which we can help you with. A headache on the other hand, is a pain you feel inside your head.
“But by far the commonest headache we humans suffer from is called a tension headache. Over half the adult population get one or two a month and some poor unfortunates get many more.”
Your headache may be caused by a cold or flu virus, the NHS said.
Other causes of headaches include stress, bad posture and not eating regular meals.
Eyesight problems and drinking too much alcohol could lead to headaches, too.
You could reduce headache pain by taking painkillers. But, taking too many painkillers could cause headaches themselves.
If you have a severe headache, and your jaw hurts while eating, you should see a GP urgently, the NHS said.
See a GP if you’re also having blurred or double vision, or if your scalp feels sore.
Go to A&E immediately if you’re having extremely painful headaches and suddenly find it difficult to remember things.
Call 999 if you lose your vision, feel drowsy, have a high fever, a stiff neck or if the white part of your eye becomes red.