Thanks Jo55. Ah, so it's the sweating issue. You are right about getting advice, but 99.99% of the time my doctors will say "we don't understand these things" nor do they provide much in the way of options, especially in the case of FMS, MCS and PN, that's why people self-treat! In fact two neurologist have pretty much booted me out of their offices and will not address PN--and that's the thanks I get for working in health care for 30 years. I do have a great deal of trouble sweating and it is only after two months of sauna use that I have started to sweat, so maybe it is something that can be re-learned. The manufacturer of my sauna recomended that I hydrate with Gatoraid or eat dulse which I've been doing. Perhaps that's is why I've started sweating. Hopefully am not doing any harm in the process. One thing that a local sauna guy told me is that most people use the suana a too high a temperature. The ideal temp is below 50 centigrade. The lower the temp, the deeper the heat penetration, and that is just plain ol' physics because longer wavelenth energy is less readily attenuated.