I had several visits to A and E/some four years.When you notice the symptoms try to swallow and snort your nose several times/nromally immediate response.I feel that a short course of Potassium/bananas regularily    etc should work.Beta blockers are bad news!     Brian Cox

I found after 5 A@E visits some two years later I gave up medication.Need to snort my nose(as in diving) or passenger flying. But oabove all a little potassium for a few weeks succeded in stopping it altogether.Tablets were bnot the answer. I am sure the medication did no goodBrian Cox