I have a feeling I could tolerate more cayenne right now. I think the most important part is how it feels after it's into your body, not the burning of the mouth, lips, throat, etc.
I plan to try to increase it soon, up to 3/8 tsp 3x a day, and I have a feeling it'll work because I don't have as much gas now or the bowel speed increase I once got on the 90k cayenne, before I was on the IP. Just like Uny said, when I'm on the IP, I should be able to tolerate a higher cayenne dose.
It may be a better idea to take my dose in less water, to make less mouth burning, and then drink more plain water afterward. Good to hear from you.