5 Rare Pain Disorders

Approximately 50-75 million Americans suffer from persistent chronic pain. While much of this pain is from more well-known disorders and diseases such as arthritis, fibromyalgia, and chronic back pain, there are others who suffer from rare pain disorders.

1. Reflex Sympathetic Dystrophy (RSD) (also known as Complex Regional Pain Syndrome). This is a mysterious chronic condition characterized by burning pain and abnormalities in the sensory, motor and autonomic nervous systems. It causes pain, swelling and limited movement, most often in the limbs. It may develop after an injury, such as a broken bone, but the severity of the pain is out of proportion to the injury and continues even after the injury has healed. Therapy for RSD is often ineffective and many people with the condition have a poor quality of life.

2. Erythromelalgia. This is a rare disorder characterized by burning pain, intermittent heat, and redness of the extremities (primarily the feet). These symptoms may be episodic or continuous in nature. Although erythromelalgia typically affects both sides of the body, it may sometimes involve only one side. The specific underlying cause of erythromelalgia remains unknown. However, the condition is thought to result from vasomotor abnormalities or dysfunction in the normal narrowing and widening of the diameter of certain blood vessels, leading to abnormalities of blood flow to the extremities.

3. Central Pain Syndrome. This is a neurological condition caused by damage to or dysfunction of the central nervous system causes. It causes disabling pain often characterized by burning with brief, intolerable bursts of sharp pain, aching pain, and "pins and needles." The syndrome can be caused by a stroke, multiple sclerosis, tumors, epilepsy, brain or spinal cord trauma, or Parkinson's disease. The syndrome may affect a large portion of the body or may be more restricted to specific areas, such as hands or feet. Pain is typically constant and is often made worse by touch, movement, emotions, and temperature changes (usually cold temperatures). Central pain syndrome often begins shortly after injury or damage, but may be delayed by months or even years, especially if it is related to post-stroke pain. Pain medications often provide some reduction of pain, but not complete relief of pain. Tricyclic antidepressants or anticonvulsants can also be useful, as well as lowering stress levels.

4. Paroxysmal Extreme Pain Disorder (PEPD). Originally named Familial Rectal Pain Syndrome, this rare disorder is characterized by pain in the mandibular, ocular and rectal areas. The most distinctive feature of PEPD is episodic burning pain of these regions. While pain often originates or is centered in these areas, it can also spread or be diffuse in nature. Women with the disorder who have also given birth describe PEPD pain as worse than labor pain.

5. Glossopharyngeal Neuralgia (GN). This is a rare pain syndrome that affects the glossopharyngeal nerve (the ninth cranial nerve that lies deep within the neck). It is characterized by sharp, stabbing pulses of pain in the back of the throat and tongue, the tonsils, and the middle ear. The excruciating pain of GN can last for a few seconds to a few minutes, and may return multiple times in a day or once every few weeks.  Many individuals with GN relate the attacks of pain to specific trigger factors such as swallowing, drinking cold liquids, sneezing, coughing, talking, clearing the throat, and touching the gums or inside the mouth.  GN can be caused by compression of the glossopharyngeal nerve, but in some cases, no cause is evident.

What to Do

While scientists pursue research seeking more effective treatments for these rare pain disorders, there are some things you can do right now.

Living with a chronic, painful condition can be challenging, especially when your friends and family don't believe you could be feeling as much pain as you describe. Share information from reliable sources about your condition with those close to you to help them understand what you're experiencing.

Take care of your physical and mental health by following these suggestions:

  • Maintain normal daily activities as best you can.
  • Pace yourself and be sure to get the rest that you need.
  • Stay connected with friends and family.
  • Continue to pursue hobbies that you enjoy and are able to do.

Keep in mind that your physical health can directly affect your mental health. At times, you may need more tools to deal with your emotions. Therapists or behavioral psychologists may be able to help you put things in perspective. They can also teach you coping skills that may help you, including relaxation techniques.

Consider joining a support group, where you can share experiences and feelings with other people. Ask your doctor what support groups are available in your community.


"Central Pain Syndrome." National Institute of Neurological Disorders and Stroke. Web. 23 Apr. 2010. http://www.ninds.nih.gov/disorders/central_pain/central_pain.htm

"Erythromelalgia." National Organization for Rare Disorders. Web. 23 Apr. 2010. http://www.rarediseases.org/search/rdbdetail_abstract.html?disname=Erythromelalgia

"Expectations of Pain: I think, therefore I am." National Institutes of Health. Web. 23 Apr. 2010. http://www.ninds.nih.gov/news_and_events/news_articles/news_article_pain_perception.htm

Glossopharyngeal Neuralgia Information Page. National Institutes of Neurological Disorders and Stroke. Web. 23 Apr. 2010. http://www.ninds.nih.gov/disorders/glossopharyngeal_neuralgia/glossopharyngeal_neuralgia.htm

Klippel Feil Syndrome Information Page. National Institutes of Neurological Disorders and Stroke. Web. 23 Apr. 2010.  http://www.ninds.nih.gov/disorders/klippel_feil/klippel_feil.htm

Mayo Clinic Staff. "Complex Regional Pain Syndrome." MayoClinic.com. http://www.mayoclinic.com/health/complex-regional-pain-syndrome/DS00265/DSECTION=causes

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Rajkumar S.Vincent, Fonseca Rafael, Witzig Thomas E. "Complete Resolution of Reflex Sympathetic Dystrophy with Thalidomide Treatment." Arch Intern Med. 161 (2001). 2502-2503