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Sleep Problems 101

Restless Legs Syndrome and PLMD
Sufferers of restless legs syndrome (RLS) feel a crawling, burning, itchy, or prickling sensation in their legs when resting for long periods, especially in the evening.

What would you think if someone told you they felt like they had bugs crawling around in their leg muscles when they tried to go to sleep? You might be prompted to look up the phone number of a psychiatrist. But more often than not, this symptom is related to restless legs syndrome (RLS).

Moving the legs seems to help alleviate the discomfort, but to do so results in the person frequently awakening from sleep. And that, of course, leads to fatigue during the daytime.

Of the 12 million Americans with RLS, most are middle-aged adults, although the condition can occur at any age. RLS might also be suspected if similar symptoms appear among these high risk groups:

The symptoms of restless legs syndrome (RLS) and periodic limb movement disorder (PLMD) resemble each other, but with some differences. A creepy crawly sensation in the legs, for example, is a hallmark of RLS but not PLMD. While each is considered a separate disorder, the RLS Foundation estimates that 80 percent of those with RLS also experience PLMD.

  • Children who have "growing pains," or those labeled hyperactive
  • Pregnant women, especially those in their third trimester
  • Persons with a family history of RLS
  • People who have iron deficiency, anemia, diabetes, kidney failure or rheumatoid arthritis

Improvement of RLS may occur with regular exercise and reduced caffeine consumption. Most often, RLS is treated with prescription medication and relaxation techniques.

Periodic Limb Movement Disorder (PLMD)

Does your bed partner ever complain that your legs suddenly jerk during sleep? One possible cause might be that you're dreaming of kicking the winning goal in a World Cup Soccer match, but more likely, you have periodic limb movement disorder (PLMD).

Sure, getting a diagnosis of PLMD is not as exciting as winning the World Cup, but at least your sleeping partner will be able to get a better night's sleep if you address the problem. And you will, too.

The involuntary movements of PLMD can occur every 10 to 60 seconds and usually happen in the first half of the night during NREM sleep. The movements themselves are not harmful, except perhaps to your bed partner. The main disadvantage is frequent waking, which leads to daytime fatigue. About one in three people over age 60 has PLMD. Treatment is the same as for restless legs syndrome.

If your limb movements take you up out of bed and around the house, you’re sleepwalking. Learn about this disorder on the next page.

For more information on how to get a good night's sleep, see:

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.