Trigeminal neuralgia

Definition

Neuralgia describes a variety of rare and painful conditions in which shooting, stabbing, burning, pain; electric-like shocks; or tingling, pins and needles, or numbness occur along the course of a nerve, usually in the head or neck.

Description

Neuralgia attacks tend to by cyclic, often coming and going without warning. They can last for minutes, hours, days, or longer, depending on the patient, and range from mild to debilitating. Often, no physical cause can be found, although some forms of neuralgia may be triggered when nerves are compressed by injuries, arteries, tumors, or, in rare cases, as the result of nerve damage from multiple sclerosis . Neuralgia is an uncommon condition, with trigeminal neuralgia occuring most often. Other types are occipital neuralgia, glossopharyngeal neuralgia, and postherpetic neuralgia. Most neuralgia patients are 50 or older, although younger patients can be affected as well.

Causes & symptoms

Most neuralgias appear suddenly, with no apparent physical basis for the pain, which can be severe. Other neuralgias may follow an injury, with pain, burning, tingling, or numbness in whatever part of the body the affected nerve supplies.

Glossopharyngeal is a relatively rare neuralgia, marked by recurring attacks of severe pain that occur for no apparent reason in the throat, ears, and neck. Glossopharyngeal neuralgia patients also tend to be middle-aged, but are more often male than female. The attacks can occur without warning, but, like other facial neuralgias, can also be triggered by sneezing, swallowing, talking, yawning, or clearing the throat.

Occipital neuralgia is caused by pain from one of the two occipital nerves that supply the back of the head. Unlike TN or glossopharyngeal neuralgia, occipital neuralgia may occur in conjunction with muscle-tension or migraine headaches, with the spasms of nerve pain on top of more-or-less continual aching.

Although most neuralgias have no known cause, one type, postherpetic neuralgia (PHN) is only seen following an outbreak of shingles, a painful, blistering rash caused by the Herpes zoster virus, the same virus that causes chicken pox. Herpes zoster lives in nerve tissue, and never goes away, even after the initial outbreak of chicken pox has disappeared. Older people, especially those with weak immune systems, can suffer a relapse, with the rash appearing along the course of the nerve that is affected. This produces the searing pain of neuralgia, which can be made even worse by the touch of clothing, bedclothes, or another person. PHN and TN are the most common types of neuralgia.

Diagnosis

Physicians begin with a thorough examination, and often include a CAT scan or MRI. These will sometimes uncover an artery or tumor that is compressing the nerve and creating the symptoms, but very often no obvious medical problem is found. In addition, trigeminal neuralgia can be identified by several distinctive traits, many of which apply to other neuralgias as well:

• The patient has attacks of pain in the face that last less than two minutes.
• The pain follows the path of the trigeminal (or another) nerve.
• The pain is described as sudden, sharp, stabbing or burning, and severe.
• The pain may be triggered by certain activities.
• There are no symptoms between attacks.
• In many patients, TN can be positively diagnosed if the drug carbamazepine (Tegretol) diminishes the pain of an attack.

Glossopharyngeal neuralgia is identified in the same way as TN, that is, the patient complains of stabbing, spasmodic pain that follows the Glossopharyngeal nerve. A positive diagnosis is usually achieved if the pain stops when the nerve is blocked with a local anesthesia.

Occipital neuralgia is caused by pain from one of the two occipital nerves that supply the back of the head. Unlike TN or glossopharyngeal neuralgia, occipital neuralgia may occur in conjunction with muscle-tension or migraine headaches, with the spasms of nerve pain on top of more-or-less continual aching. X rays and CAT scans can help indicate if the nerve is compressed; numbing the nerve with anesthetics can pinpoint the cause.

Treatment

Trigeminal neuralgia was identified almost 2,000 years ago. Early treatments, like most medicine in those days, were mostly topical (applied to the skin) and ineffective. Today, the most effective treatments for neuralgia are allopathic, but alternative therapies may help support the patient's general well being and improve overall health.

Nutritional therapy

B-complex vitamins, taken orally or given by intramuscular injection, are important for a healthy nervous system, and may supplement medical treatment. A whole foods diet with adequate protein, carbohydrates, and fats that also includes yeast, liver, wheat germ , and foods that are high in B vitamins is important. Essential fatty acids , such as flax or fish oil , may also help reduce inflammation.

Herbal therapy

Capsaicin cream, made from capsicum, a substance found in hot peppers, has sometimes been helpful in desensitizing painful areas in postherpetic neuralgia. Capsaicin may diminish the amount of "substance P," a chemical used by nerves to send pain signals to the brain. St. John's wort , an antidepressant, may help the other forms of neuralgia, which are often treated allopathically with tricyclic antidepressants (TCAs)

Acupuncture

Some patients found that acupuncture was helpful in treating their neuralgia pain, especially that of postherpetic neuralgia. Others were unable to obtain relief from the procedure.

Chiropractic

Chiropractors can manipulate the jawbone, neck or spine to treat neuralgia pain. Like most alternative treatments for neuralgia, this is effective for some patients and not for others.

Homeopathy

Homeopathic treatment can also be tried. An experienced homeopathic practitioner will prescribe remedies to bolster the paitient's general health, tailoring remedies to the patient's overall personality profile as well as specific symptoms.

Other alternative therapies

The pain of neuralgia may also be relieved by hydrotherapy (hot shower or bath), deep massage, reflexology (massaging reflex points in the feet relating affected painful areas in the body) or yoga exercises. In addition, guided imagery , biofeedback therapy, and hypnosis may be beneficial. Patients should also consider t'ai chi , qigong, and other movement therapy .

Patients may also be helped by transcutaneous electrical nerve stimulation (TENS), a relatively new treatment in which a weak electric current applied to the skin interferes with the nerve's ability to send pain signals to the brain. Although still controversial, initial results, especially for postherpetic neuralgia, are promising.

Allopathic treatment

Once a diagnosis of neuralgia has been established, physicians prescribe drugs to alleviate the pain. The anticonvulsant drug carbamazepine (Tegretol) is often an effective treatment for TN, relieving or reducing the pain within a day or two. Unfortunately, it can also cause dizziness, drowsiness, nausea, and double vision, to name just a few of its more common side effects. If Tegretol is not well tolerated, doctors can try another anitconvulsant, like gabapentin (Neurontin), antispasmodics like baclofen (Lioresal), or anti-anxiety drugs like clonazepam (Klonopin). These drugs are also frequently prescribed for other forms of neuralgia as well.

Injecting local anesthetics into the nerve can stop the pain for a few hours, and for some patients this is effective for a much longer time. Lidocaine cream may be somewhat helpful in treating PHN, probably by temporarily desensitizing nerves just under the skin. Lidocaine may also help atypical forms of TN. Alcohol and glycerin injections that destroy part of the nerve (and thereby its ability to transmit pain) may also be an option.

One particularly unpleasant, but evidently successful, method of treating neuralgia seems to be desensitization. This means that if a patient is bothered by the touch of clothing on the skin, the therapist may rub a towel briskly over the area for a few minutes. If the patient has trouble tolerating heat or cold, warm or cold water may be applied. Although initially quite painful, this method gradually diminishes the frequency and intensity of the patient's pain, apparently by overwhelming (and eventually reducing) the nerve's ability to send messages to the brain.

For PHN, the best treatment seems to be prevention. People with shingles should see a doctor as soon as the rash develops so they can receive treatment to ease the severity of the outbreak and minimize the risk of developing postherpetic neuralgia. It is not clear, however, whether treatment can prevent subsequent neuralgia. If PHN does develop, TCAs--especially amitriptyline--are often helpful. It's important to stress, though, that early attention to either a shingles outbreak or PHN episode will reduce the incidence and severity of future attacks. Some patients receive complete pain relief after treatment. Others are able only to reduce the pain (to greater or lesser degrees), while for a very few treatment is completely ineffective. For these patients PHN becomes a lifelong, chronic condition; most cases, however, moderate on their own and disappear within five years.

As a last resort, surgery may bring relief for those neuralgia patients unhelped by pharmaceuticals. Most procedures try to reduce the nerve's ability to send pain signals to the brain. One of the most promising is dorsal root entry zone (DREZ) lesioning, which uses radio frequency to disrupt the nerves that are causing pain. Some studies showed that as many as 80% of DREZ patients were helped.

Expected results

Only a few neuralgia patients will not be helped by some combination of drugs and surgery. PHN, in particular, tends to fade away on its own, and only 2-3% of patients have pain that lasts a year or longer. For those unfortunate few, however, PHN can become a lifelong, debilitating condition.

Key Terms

Desensitization

A method of pain reduction that overstimulates sensitive nerves, eventually reducing or eliminating their ability to send pain signals to the brain. Capsaicin is also used to desensitize neuralgia patients.

Dorsal root entry zone (DREZ)

The dorsal root entry zone is the gateway between nerves and the brain. In this surgical procedure, the root of an affected nerve is destroyed, stopping pain signals from that nerve to the brain.

Glossopharyngeal neuralgia

An uncommon disorder characterized by stabbing, excruciating pain in the throat, ear, and/or jaw. It is triggered by swallowing, talking, yawning, or clearing the throat.

Occipital neuralgia

Stabbing, burning pain in the back of the neck, head, and scalp caused an inflamed or diseased occipital nerve.

Postherpetic neuralgia

Severe, persistent pain that follows a shingles outbreak.

Shingles

A painful blistering rash caused by the herpes zoster virus that traces the path of a nerve; it is common in elderly patients.

Transcutaneous electrical nerve stimulation (TENS)

A treatment for chronic pain that uses electrodes on either side of an affected area to impair the nerve's ability to send pain signals to the brain. pathways.

Trigeminal neuralgia or tic douloureux

An affliction of the trigeminal or fifth cranial nerve. The condition is characterized by attacks of shooting, stabbing pain on one side of the face. These episodes are triggered by touching the affected area.

Further Reading

For Your Information

Books

• Althoff, Susanne, Patricia N. Williams, Dianne Molvig, and Larry Schuster. A Guide to Alternative Medicine. Lincolnwood, IL: Publications International, Ltd., 1997.
• Gottlieb, Bill, ed. "Sciatica." In New Choices in Natural Healing: Over 1,800 of the Best Self-Help Remedies from the World of Alternative Medicine. Emmaus, PA: Rodale Press, 1995.
• Loeser, J. "Cranial Neuralgias." In The Management of Pain. 2nd ed. Philadelphia: Lea & Febiger, 1990.
• "Neuralgia." In The Hamlyn Encyclopedia of Complementary Medicine. Great Britain: Reed International Books Limited, 1996.

Periodical articles

• Fields, H. "Treatment of Trigeminal Neuralgia." The New England Journal of Medicine 334 (April 1996): 1125-1126.

Organizations

• American Chronic Pain Association. PO Box 850, Rocklin, CA 95677. (916) 632-0922.
• National Chronic Pain Outreach. PO Box 274, Millboro, VA 24460. (540) 997-5004.
• Trigeminal Neuralgia/Tic Douloureux Association. PO Box 340, Barnegat Light, NJ 08006. (609) 361-1014.

Gale Encyclopedia of Alternative Medicine. Gale Group, 2001.