Regrettably, I have had to relearn how to ride a bike. My wife didn't believe that I rode a bike before when I was younger. It was about 4 years ago that I took up bike riding again and I needed to relearn how to ride it. I felt shaky at first when I was riding it, and a little embarrassed to say that my wife had to "train" me. 

It seems this happens to me with chess. It's as if I get "Youngheimer's" and need to refresh my brain on the basics. For instance, as per chess.com I believe I have the ability to play at the 1800-1900 level (in chess.com, not FIDE or USCF?) but now I feel I'm back to around 1300. I forget the tactics that I've learned and resort to amateur type play. Does anyone have a cure? (or at least a panacea?)

Thanks in advance, and may your day be blessed. 

Playing a lot of games is the best way to knock the rust off :)

Likely a lot of the strategy is still there, but you need to refresh your calculation and tactical awareness (I would guess).  So I'd guess tactic puzzles will help.

I played a national master (2200+ uscf) at my club who hadn't played in 10 years.  He was maybe around 1700-1800 strength, but when there was something strategic needed to be done in the position he make the move instantly heh.  Only reason he was worse was due to tactics and calculation it seemed.

Thanks!

I agree that can help. I looked at 2 puzzles from Lev Alburt's classic 300 most important chess positions and it got the brain juices going. It seems more play and study go hand in hand. I'm noticing I'm losing "won" games because I'm not seeing the easy move on the board. I just finished playing a guy for 47 moves where I allowed his king to get across the top rank, and if one gives someone enough chances, it'll cost the person like it did me...

With a bit of practice you should be able to get somewhat close to your previous level.  The problem is that your previous level wasn't nearly so high as you believe it was.

Well, in one case you're right, maybe I'm believing I'm better than I am. As per the "correspondence" chess here on chess.com, my rating is 1774 as of Jun 1 2009. I was playing "live chess" in order to play more games and actually finish and also I was trying to learn how to play against time. My comment wasn't so far off in this case...