This will sometimes happen a few times a day, and ill often see her limping due to a bad cramp earlier in the day. theres no particular time it happens, seems to come on totally at random.
visits to the doctors havent helped at all, the only thing they have done is tested her for diabetes, which she doesnt have.
Shes also an identical twin, her twin doesnt have any such problems.
What could potentially be causing this, and is there anything she can do, other than continuing to pester her GP?
This may sound simple but has she had her potassium checked? My grandmother was getting horrible leg cramps so I pulled out her last lab work and sure enough her K was low, no one mentioned it because it was just slightly low. After getting her an over the CPU yet potassium supplement and having her eat a banana or two a day no leg cramps in over 2 years when it was previously a daily thing. Same with my husband, I think being in south Texas we sweat a lot of stuff out so it's low, he started a low dose of K and no more leg cramps. Hope this may help!
Of this may possibly be the problem just have her get over the counter potassium supplements and take them according to the directions of the one you get. That way she is getting K and not whatever is in the multi. A multi is ok as well but get just K to see if it helps the cramps.