What Causes Prickly Pain Throughout The Body Of An Elderly Person?

My 89 year old mother hAS BEEN EXPERIENCING THESE VERY STRANGE SYMPTOMS. sHE SAYS IT IS L IKE AN ELECTRICAL SHOCK THAT GOES FROM THE TOP OF HER DOWN THROUGH HER BODY TO HER TOES. I THINK IT IS MAINLY ON HER RIGHT SIDE. sHE HAS ATRIAL FIBILATION AND HER BLOOD PRESSURE SEEMS TO BE QUITE LOW. sHE IS IN A NURSING HOME, BUT NO ONE SEEMS TO B E TO CONCERNED. sHE RECENTLY HAD AN EEG AND THEY SAID SHE DID NOT HAVE A STROKE OR HEART ATTACK. DO YOU KNOW WHAT COULD BE THE CAUSE. sHE IS ALSO ON DIURETICS FOR WATER RETENSION.