Not that I am aware of. I would be cautious using it around mucous membranes.
It's in so many creams I use, I say just as the person aboe me, it's fine as long as you kee out of eyes, nose and mouth. I use a hot cream that has capsacin, what bear soray is made if, and use rubber gloves to apply.
I just looked it up. Yes, it can be bad for your liver, and says not to use long term. Too bad they don't mention if long term is 2 weeks or 6 months. Good luck. I don't know what you use it for but for muscle cramps I've had great luck with magnesium oil and a blue cream with essential oils i get from amazon. The dotella brand is 3 to 4 times the price.