My only real experience with HyperT Mark was with my nasty cow of a neighbour in summer 2007 (now thankfully moved). Cat called Zimmy. Do you remember by any chance? Bloody nightmare but, from what I recall, the continuing meds where not expensive, it is more likely the cost of continuing blood tests to monitor situation that brings the cost up to £60 p/mth? The blood tests should be less frequent as the condition is stabilised with meds?