A headache is pain or discomfort that occurs in or around your head, including your scalp, sinuses, or neck. Nausea is a type of discomfort in your stomach, in which you feel like you need to vomit.

Headaches and nausea are very common symptoms. They can range from mild to severe.

Headaches and nausea sometimes occur together. In some cases, they may be a sign of a serious medical condition that requires immediate treatment. Learn how to recognize a potential emergency medical situation.

What causes headache and nausea?
Migraine headaches are a common cause of combined headache and nausea. Migraines can cause a variety of symptoms, including nausea, dizziness, sensitivity to light, and severe headache pain. They’re often preceded by a visual or sensory disturbance, called an aura.

Other conditions associated with headache and nausea include dehydration and low blood sugar. Dehydration can occur when you don’t drink enough fluid.

Low blood sugar can develop for a variety of reasons, including excessive alcohol consumption, medication side effect, severe liver or kidney disease, long-term starvation, and hormonal deficiencies. If you have diabetes, taking too much insulin can also cause low blood sugar.

Other conditions that can lead to headache and nausea include:

stress or anxiety
food poisoning
food allergies
high blood pressure
diabetic ketoacidosis
scarlet fever
strep throat
alcohol withdrawal delirium
early pregnancy
infections, such as the common cold or flu
brain infections, such as meningitis or encephalitis
skull fractures
Colorado tick fever
malignant hypertension (arteriolar nephrosclerosis)
poisoning due to black widow spider venom (black widow spider bites)
Ebola virus and disease
SARS (severe acute respiratory syndrome)
yellow fever
carbon monoxide poisoning
end-stage kidney disease
Addisonian crisis (acute adrenal crisis)
medullary cystic disease
West Nile virus infection (West Nile fever)
adult brain tumor
brain abscess
acoustic neuroma
fifth disease
traumatic brain injuries, such as concussion or subdural hematoma
leptospirosis (Weil’s disease)
subarachnoid hemorrhage
low blood sodium (hyponatremia)
brain aneurysm
dengue fever
HELLP syndrome
hepatitis A
toxic shock syndrome
acute mountain sickness
stomach flu (gastroenteritis)
premenstrual syndrome (PMS)
menstrual period
Consuming too much caffeine, alcohol, or nicotine can also cause headache and nausea.

When should you seek medical help?
In many cases, mild to moderate headaches and nausea resolve on their own with time. For example, most cases of the common cold and flu resolve without treatment.

In some cases, headache and nausea are signs of a serious underlying health condition. You should seek immediate medical attention if you experience a very severe headache or if your headache and nausea worsen over time.

You should also see a doctor if you experience any of these symptoms along with your headache and nausea:

slurred speech
neck stiffness and a fever
vomiting for more than 24 hours
no urination for eight hours or more
loss of consciousness
If you suspect you need urgent care, seek help. It’s better to be safe than sorry.

If you experience headaches and nausea on a frequent basis, even if they’re mild, make an appointment with your doctor. They can help diagnose your symptoms and recommend a treatment plan.

How are headache and nausea treated?
Your recommended treatment plan for headache and nausea will depend on the cause of your symptoms.

If you have an underlying medical condition, your doctor will try to treat or manage it. For example, they may recommend lifestyle changes, medications, or other treatments to help prevent or relieve the symptoms of migraines.

In some cases, lifestyle changes or home remedies may help relieve your symptoms. For example:

If you experience migraine headaches and feel a migraine coming on, stay in a dark and quiet room, and place a cloth-covered ice pack on the back of your neck.
If you suspect your headache and nausea are caused by stress, consider participating in stress-relieving activities, such as taking a walk or listening to calming music.
If you suspect you’re dehydrated or your blood sugar is low, take a break to drink or eat something.
Over-the-counter pain relievers, such as ibuprofen or acetaminophen, may help relieve your headache. Aspirin may be too tough on your stomach and can cause stomach upset.

How can you prevent headache and nausea?
While some cases of headache and nausea are hard to prevent, you can take steps to lower your chances of experiencing them. For example:

Get enough sleep.
Stay well-hydrated.
Eat a well-balanced diet.
Avoid consuming too much caffeine or alcohol.
Lower your odds of getting the common cold and flu by washing your hands regularly.
Reduce your risk of head injury by wearing a seatbelt while traveling in motor vehicles and protective headgear while riding your bike or participating in contact sports.
Identify and avoid your migraine triggers.
To identify your migraine triggers, consider keeping a journal in which you write down your daily activities and symptoms. This may help you to learn which foods, activities, or environmental conditions set off your symptoms.