I find Beljum Budder can be irritating if it gets up inside, which the way my anatomy is, it can. If it doesn't migrate, it's fine on all external areas, including the mucous membranes of the labia.

Nubutte is a very healing salve and it's great to treat any chafed areas, but as I said it doesn't really help me as a lubricant. But it's designed as a lubricant and some people use it that way.

I don't use Chamois Butt'r because of the paraben preservatives, particularly with my health issues, but never found it irritating when I did use it.

Lots of chamois lubes say right on the label both that they're "suitable for men and women" and "do not apply to mucous membranes." I actually sent an inquiry about one product, I forget which, and got a reply back from some guy, saying that both statements were correct. I managed to restrain myself from replying with some rude comment about his cluelessness about female anatomy.

Possibly someone with porn star-like anatomy might be able to ride without any mucous membranes contacting the chamois or being pressed against each other ... in which case either cornstarch or some of the harsher lubes would be fine ...