Headaches and nausea
Nausea or feeling sick is a common symptom accompanying a migraine or bad headache. It is estimated that around eight out of 10 people who have migraines experience nausea and five out of 10 have some vomiting with their migraines.
Nausea and sickness can also be experienced with headaches, but the headache may not always be the cause of those symptoms.
Seek medical advice if you have concerns about migraine, headaches and nausea.
What kind of headaches might cause nausea?
There are multiple conditions and illnesses that can cause headaches with nausea or vomiting. The doctor will ask about your specific symptoms and history. What you tell the doctor will help determine whether your headache and nausea are migraine-related or the result of another condition or illness. Other conditions that might cause headaches and nausea include:
- Colds, flu or stomach bugs. Common viruses that cause cold, flu and stomach bugs, or gastroenteritis, can cause headache and nausea. Both can range in intensity from mild to severe. Unlike migraines, these conditions are often accompanied by other signs of viral illness. For instance you may have a runny nose, diarrhoea, chills, aches and pains, and a fever.
- Meningitis. A headache accompanied by extreme sensitivity to light and nausea may sound like a classic migraine. However, if it is also accompanied by a stiff neck, or vomiting, with or without a fever, it could be meningitis.
- Cluster headache. Nausea is one of the factors commonly used to distinguish between migraines and other types of headache. That includes tension headaches and cluster headaches. However, there is some evidence that suggests some people with cluster headaches do experience nausea when attacks occur. Cluster headaches are repeated, excruciating, one-sided headaches.
How are migraines and nausea related?
Millions of people suffer from migraines with nausea. However scientists have not been able to determine exactly why.
Current thinking suggests that migraines occur when certain nerves in the brain signal blood vessels on the brain’s surface to enlarge. Changes in oestrogen levels are also thought to play a role. That may be why more women than men experience migraines. Blood vessels on the brain’s surface also swell when levels of the neurotransmitter serotonin drop. It’s possible that people with low levels of serotonin may be more likely to experience migraines. Low levels of serotonin may also be linked to motion sickness and nausea.
Certain groups of people are more likely to experience nausea with a migraine. This includes women and people who are prone to motion sickness. Between 5% and 20% of the general population experiences motion sickness. And movement-related nausea is experienced by about 50% of the people who get migraines.
Certain types of migraine are likely to produce symptoms of nausea or vomiting, as are some migraine variants. These include:
- Migraine with or without aura. Migraines without aura are more common and may cause severe head pain, vision problems, vertigo, sensitivity to light and nausea. People who have migraines with aura typically experience warning symptoms 20 minutes to an hour before the headache begins. These warning symptoms include visual disturbances and dizziness
- Abdominal migraine. Most migraines cause headaches. In rare instances children experience migraines that cause stomach pain instead. When attacks occur they can cause children to feel sick or vomit. An attack may also cause a loss of appetite. People who experience abdominal migraines as children are likely to have migraine headaches in adulthood
- Benign paroxysmal vertigo of childhood. This migraine variant is most often seen in toddlers. When it occurs the toddler will seem to suddenly lose balance and may be unable to walk. The condition often causes children to vomit. The vertigo resolves after a period of a few minutes to several hours
- Cyclic vomiting syndrome. This troubling condition occurs most often in children, though adults can also be affected. Cyclic vomiting syndrome causes people to have periods of nausea and vomiting that can last anything from hours to days
The exact relationship between cyclic vomiting syndrome and migraine has not been determined. However, the two conditions do seem to be connected. They share many of the same triggers including stress. Many children who have cyclic vomiting syndrome go on to develop migraine headaches or have relatives who suffer from migraine headaches.