I have been having some kind of muscular attack/seizure? off and off for over 5 years. I am on a potassium supplement , but when I have gone to ER for these attacks which can be quite severe with hyperventilation and chest spasms, the only consistent abnormality was very low potassium. I was given a potassium tablet and sent home. I have been to cardiologists, neurologists, pulmonologists, with no answer to the problem.