Can Nitrous Oxide suddenly stop working?

[stillwelny]

I have been successfully taking nitrous oxide for most dental procedures from the same dentist for over 20 years. The last 3 visits, I had very little reaction to the gas even when it was turned up as high as it could go. Is it possible to get immuned to it?

 

[Dr. Daniel]

Our body changes over the years and with it also our ability to apsorb and metabolise food and other substances. I do not know you personally, but factors like gaining weight, smoking, using medications have an affect.