Let me begin by advising you not to take my advice. I'm just some retarded a-hole writing anonymously on the internet. You should really ask a doctor or something about this crap.
Ever since 1999, I have been suffering from restless leg syndrome. It's one of those diseases that sounds made up and even stupid. The kind of disease you reference when talking about diagnoses run amok. I agree, it does sound stupid. "Creepy-crawling"? What kind of symptom is that?
In any event, I experienced it on my religiously-affiliated vacation in Chile, where it got much worse than it had ever been before. It subsided a bit while I was in college, but came back with a vengeance when I started law school and has (had) remained with me, at a pretty debilitating level ever since. There were days in a row where I would not get more than a few hours' sleep because of the jimmy legs.
I tried a number of treatments: neurontin and other anti-seizure drugs, sleeping pills, warming leggings, but to no avail. I even tried multi-vitamins, potassium, iron supplements, and got bupkus. Nothing seemed to help. The only way I could even get some sleep was to take sleeping pills. (By the way, Ambien CR is awesome.)
Well, due to the wonderful free-market healthcare system we currently enjoy, I ended up spending a month without insurance. During that month, I didn't refill my asthma medication, Singulair because it costs $180 to fill. That's $6.00 per pill. That's like three years of XBox live membership. And so what if I got sick every single time I had previously neglected to take my Singulair on a daily basis? Screw that.
Despite my experience, I did not get sick and my restless legs went away. I spent an entire month without the constant pain and lack of sleep they usually bring. Then, I got insurance again, refilled my Singulair and started up again. That same day, I had the worst restless legs I've had in months. Not wanting to make serious medical decisions on a fluke, I took it again the next day with the same result. It sucked balls. So, I stopped taking it. It took about five days to completely wear off, but my restless legs are for the most part gone again. Now, I can return to looking down on people who have crap illnesses. You have depression? There's no such thing, you're just being a pussy. What's that? You're saying I take Lexapro? I take that for my crippling emotional cancer. I see how you would confuse the two.
In summary, Singulair causes restless legs. And since I'm clearly a qualified physician and not just some anonymous idiot blogging on the internet, you can take that to the bank.*
*To repeat: I'm not really a doctor. In fact, I'm just some retarded a-hole writing from my own experience and not a bit of knowledge, education, training, research, or qualification. DO NOT TAKE MY ADVICE! I cannot emphasize this enough.