A headache and nausea is a powerful combination – and one that is not uncommon. In fact, these two symptoms are so closely linked that some people develop a headache when they are sick at their stomach and others develop nausea when they get a headache. Most of the time, a headache and nausea are indicative of some other illness and treating the underlying illness will usually relieve the symptoms.

Causes of Headache and Nausea

Headaches and nausea are generally caused by either specific health conditions or lifestyle choices.

1. Health Conditions

• Migraines. Migraines are a leading cause of the headache and nausea combination. The exact link between migraines and nausea is being researched but there are several possibilities. First, changes in estrogen levels are thought to cause both headaches and nausea. Motion sickness may play a role. One of the leading theories is that the headache of migraines is caused by abnormal swelling of blood vessels on the brain which is triggered by decreased serotonin levels. These decreased serotonin levels may also lead to nausea caused by motion sickness.
• Flu, Cold or Stomach Flu. Viruses that cause colds and gastroenteritis are known to lead to headache and nausea. A person with a viral illness will usually have other symptoms in addition to headache and nausea. Typically, other symptoms of viral illness may include fever with chills, diarrhea and vomiting, and a runny nose if the infection is a respiratory illness.
• Meningitis. Meningitis is an infection of the spinal fluid or brain that causes an extremely severe headache and nausea. Meningitis is characterized by a fever and stiff neck. If you suspect you have meningitis, it is important that you seek medical care.
• Cluster Headache. A cluster headache is one that occurs on one side or the other. Although people do not usually have nausea with a cluster headache, some people do, so a visit to your healthcare provider can help you distinguish between a cluster and migraine headache.
• Tension Headaches. Tension headaches can be caused by physical or psychological stress. Physical activity that results in tension in the neck and shoulders can result in a tension headache. Mental stress due to lack of sleep, work stress, or decreased caffeine use can also lead to a tension headache and nausea.
• Other Causes. Other causes of headache and nausea can include elevated blood pressure, cancer, head injury, Crohn's disease, drug or medication interactions and side effects, pregnancy, infections, cardiac problems, depression and diabetes. If you suspect your symptoms may be caused by any of these problems, you should see your healthcare provider for treatment.

2. Poor Habits and Others

• Eye Strain. Eye strain is a known cause of headache and nausea. If you find yourself squinting or straining to see, you should have an eye exam by a qualified optometrist or ophthalmologist.
• Alcohol. Overuse or abuse of alcohol is a known cause of headache and nausea. Usually, nausea occurs while drinking and after; headaches associated with alcohol usually occur the next day in the form of a hangover. Alcohol can cause dehydration which can increase the intensity of a headache.
• Others. Fatigue due to lack of sleep is one very common cause of headache and nausea. If you are pregnant, morning sickness can be a leading cause of headache and nausea. For women, monthly cyclical hormonal changes can result in headache and nausea.

Remedies for Headache and Nausea

Because they are so inter-related, curing either the nausea or the headache may actually cure the other one, too. There are several things you can do to treat your headache and nausea.

• Find the Causes. Remedies for headache and nausea will depend on the cause, so the first step in treatment is to find what is causing the problem. If the headache and nausea are related to motion sickness, alcohol, or tobacco, the answer is to avoid the cause by reducing or stopping the lifestyle habit that is the problem.
• Treating Nausea. Treating the nausea may be as simple as stopping the activity that is causing you to be sick at your stomach. Slow deep breathing and meditation may help. You can also use any number of over-the-counter medications for nausea. Ginger ale or ginger tea helps some people control nausea. Some of the B vitamins (particularly B6) may help control the nausea.
• Curing Headaches. The first remedy to try for a headache is to determine if there is a lifestyle cause for the headache and then eliminate that cause. Resting quietly with your eyes closed and a cool washcloth over your eyes may provide relief. If this seems to help, be sure to have your eyes examined since headaches can result from eye strain. Finally, over-the-counter pain medications (ibuprofen, acetaminophen, or aspirin products) may help relieve an acute headache.

When to See a Doctor

Typically, headache and nausea will go away with home treatment. However, you should see your healthcare provider immediately if you have seizures, difficulty with speech or if you have numbness in your arms and legs along with the headache and nausea. You should also be seen by your doctor if the headache and nausea follow any kind of head or neck injury. See your doctor if you have a headache that is “the worst you’ve ever had” or if you have a severe headache for more than 24 hours. These symptoms can indicate a much more serious problem and should be evaluated immediately.