I'd call them and inquire if you have any unusual symptoms. Sometimes, with liver failure, you will become jaundiced (yellow skin or eyes), or have upper right quadrant pain. There are other symptoms as well, but I couldn't find the list--I'm working from memory here. Another might have been itchy skin. With the drug I take, Cymbalta, there were some cases of liver failure in a clinical trial--but in subjects who drank a "substantial" amount. They said some subjects had slightly increased ALT levels, and a very, very few had alt readings up to 20x normal! So, apparently there is quite a range that is possible and still be OK.

But you are wise to be concerned--I'd call if you notice ANY new symptoms when you start the higher dose.