Wow this is an ole post?
Leg cramps can very much be with the FM issues we have and also a few other causes. Electrolytes being one. Making sure you have taken enough Magnesium....Dr Oz states everyone should be on 250mg a day...well I increased to twice a day and found a good change in my issues. (If normal needs once me and mine needed twice)
Calcium is another ion needed in muscle function as is potassium. Getting them in your diet is important. If you are on water pills please be sure there is a potassium check and a replacement ordered for you.
The last thing that comes to mind is "vascular insufficiency"
With varicose veins... at night blood flow slows with the heart beat and all the oxygen and nutrients have been removed as it is returning from the lower body to the heart and lungs for oxygen......this is where you can have muscle dysfunction....adding heat to bring in new blood (also that is how walking it off works) and maybe getting a venous doppler done to assess the inner workings of your legs. Reflux may be prominanet there and you are not efficient in the night.
Some doctors will ask to try TONIC water everyday. To get the quinine in there as a helpful tool.....but getting to the cause I think is better then looking for a bandaid...
So, this is what came to my mind when I saw this note. Maybe it will help.
I just went through a big issue with this as I lost weight and the vascular disease I have was now in the forefront...cramps in the upper thigh (only could use heat) cause was I lost the fat that served as support to those vessels. I have since had closure and removal of them to help me move forward.....
Life always hands you a challenge, gotta try and make lemonade! Good luck, Nancy B