I was quoted 200 dollars for nitrous oxide gas, per session. i was just wondering is 200 dollars the normal price for laughing gas?

Professional fees: It is difficult to tell you what is normal and what is not. Your office chooses to charge for that part of your care, whereas other offices charge nothing and build it into their total fee schedule. If you are happy with the treatment and service you receive at that office, then consider the expense as part of the total cost of your care.

Sounds high: Sounds high. Check around locally. Perhaps your doc will match.