Do not despair, Dr Diana has created a video on Diamox and why it might stop working after a while. It’s something to do with acid or electrolyte balance, I can’t just recall at the moment but your doctor needs to take regular blood tests to make sure your balance is right. My consultant said you had to keep up with your potassium (eat a banana a day) or you may just need to take some bicarb and it’ll be up and running again. I suggest you click on the ‘video’ link at the top of the page and do a quick search for it, to be sure – worth a try ?!