He has trouble sleeping. He's always had these tingles in his legs, he tells me. They keep him awake until he passes out from exhaustion.

We are sitting on the couch one evening when they start. He is obviously uncomfortable, shifting around and bouncing his legs. "Is it your legs?" I ask quietly. He sighs. Yes, of course.

I thought it was all in his head, an excuse to stay up late. I told him to stop drinking so much caffeine, to watch his diet and not sleep so late in the day. I wasn't really helping.

Until the day I asked his mother about it. Turns out his grandmother also had RLS and that, like him, it caused her many sleepless nights. There is no cure; it grows worse with age. So I start the search. And here's what I learned:

Restless Leg(s) Syndrome, also known as nocturnal myoclonus, is a sleep-related syndrome. Discovered in the 1940s by a Swedish neurologist, the disorder affects about 10% of us and tends to run in families. Doctors aren't sure the cause of RLS; prevention and treatment of symptoms are the best they can do for now.

What they do know is that it flares up during periods of inactivity (like when you're watching TV or falling asleep), and it is associated with peripheral nerve diseases, anemia, and ADHD. Contrary to the name, RLS is not only a disorder of the legs. It can also occur in the feet, hands, and arms.

It feels like tingles, or a stirring discomfort that leaves you restless. It keeps you awake and that's the real pickle, because sleeplessness and stress make it worse. So here you are, trying to fall asleep but you start to worry that your legs will tingle and you won't get any sleep. Sure enough, the sensation of worms crawling in your legs starts. Now you really begin to worry. You stay awake for hours past bedtime, searching for relief and stressing over your condition. After hours of stress, discomfort and frustration, you pass out. The cycle continues. So what're we to do?

While RLS is not particularly painful, many sufferers self-medicate with pain relievers, alcohol, and other drugs. I can't begin to tell you how many things are wrong with that plan. Try regular exercise, yoga, meditation, and other physical activity that promotes restful sleep and stress reduction. As leighton mentions above, limiting your caffeine intake may help as well. The RLS Foundation recommends experimenting with your sleep cycle to find a more suitable bedtime. Some people seem to respond better to rising and sleeping at later hours. Acupuncture, warm baths, aromatherapy and massage may also help relieve symptoms.

If you are experiencing the symptoms of RLS, please see a physician to rule out any other medical problems.

Information from The Restless Legs Syndrome Foundation (http://www.rls.org), WebMD and Yahoo! Health.