Your doctor can usually diagnose tension headaches by asking you questions about your health and lifestyle and by examining you.

It is important to distinguish tension headaches from other headaches (such as migraines) because symptoms can be similar, but treatment may vary. Usually migraine pain is felt on only one side of the head. Tension headaches usually cause pain on both sides of your head.

Your doctor may diagnose tension headaches if you have headaches with:

• Constant pain that does not throb or pulse. You usually feel the pain or pressure on both sides of your head.
• Tightness around your forehead that may feel like a "vise grip."
• Aching pain at your temples or the back of your head and neck.

You might be sensitive to light or noise (but not both at the same time), but you will not usually feel nauseated. The pain does not get worse with activity.

Tension headaches can last any length of time from 30 minutes to 7 days. You may be diagnosed with chronic tension headaches if you have the same symptoms but have at least 15 of these headaches a month over a 6-month period.

In very rare cases, headaches can be caused by other, more serious medical conditions (such as brain tumors or aneurysms). Your doctor may order tests to rule out other causes. These tests may include:

• A lumbar puncture, a test in which your doctor uses a needle to remove a small amount of fluid from your spinal canal. The fluid is then looked at for signs of infection.
• An electroencephalogram (EEG), a test that measures and records the electrical activity of your brain by using sensors (electrodes) attached to your head and connected by wires to a computer.
• An MRI scan of your brain, a test that uses a magnetic field and pulses of radio wave energy to provide pictures of your brain.
• A CT scan of your head, a test in which a scanner directs a series of X-ray pulses through your head. This produces detailed pictures of structures inside the head.

Parents may become very concerned about headaches in children and feel that extensive testing is needed to rule out serious causes. But doctors often can evaluate children's headaches without using imaging tests. Children who have headaches will sometimes be monitored for 6 months or longer from the time of their first headache.