Chronic headaches are defined as headaches that occur on more than 15 days a month over a period of at least three months. In some cases, the symptoms occur every day or almost every day. The pain can be severe and debilitating.

The National Headache Foundation estimates about five percent of Americans experience chronic headaches. Some common types of chronic headaches include: migraine, tension and cluster.

In most cases, chronic daily headache is caused by overuse of pain medications. As the body becomes accustomed to the drugs used to treat pain, higher or more frequent doses are needed to keep the pain away. That eventually leads to a rebound headache when pain meds are stopped.

Another Cause of Chronic Headaches

Pamela Blake, M.D., a Neurologist with Memorial Hermann Northwest Hospital, says, in some cases, chronic headaches can also be caused by cranial neuralgia, a condition caused by irritation, inflammation and/or damage to one of the nerves around the head. The pain always occurs in the same part of the head. The symptoms can be severe and debilitating and are often described as sharp, burning or jolting (like an electrical shock).

Blake says two main nerves are usually affected - the occipital nerve and the trigeminal nerve. The occipital nerve runs from the top of the spinal cord and up the neck to the base of the skull, branching off to supply sensation to the scalp. The trigeminal nerve is responsible for nerve signaling and sensation in the front of the face. It breaks into several branches. The two branches most commonly affected by cranial neuralgia are the temporal nerve (supplying sensation to the side of the head) and the frontal nerve (supplying sensation to the forehead).

To make a diagnosis, Blake presses on the areas where the nerves run to assess the degree of tenderness. A second test involves the injection of a nerve block into the affected nerve. Blake says if the headache is caused by a nerve problem, this will usually bring relief, but the effect is only temporary, lasting only a few weeks. Thus, a longer-lasting treatment may be needed.

Nerve Decompression

For a more permanent solution to cranial neuralgia, Blake works with a plastic surgeon to offer a procedure called nerve decompression. The goal is to move or remove tissue (like a blood vessel or muscle) that is pressing on the nerve causing the symptoms. The procedure is typically done on an outpatient basis through minimally invasive techniques. It can take two to four hours because surgeons must be very careful to correctly identify the target nerve and avoid injuring other muscles, nerves or blood vessels.

After surgery, a catheter is placed into the area of the incision to provide pain medication to the site for five days. Once the catheter is removed, sensation gradually returns to the area. Blake says some patients experience temporary symptoms of tingling or burning. These are caused by manipulation and irritation of the nerve during surgery. Most patients reach full recovery within one to three months. According to Blake, the surgery is also performed at Memorial Hermann Northwest Hospital in Texas, Case Western in Ohio and Georgetown University in Washington, DC.

For general information on chronic headaches:

National Headache Foundation

National Institute of Neurological Disorders and Stroke