I have severe back pain due to an accident I was in over a year ago in addition to degenerative disc disease and have been on pain meds for the past year. I'm a little concerned because I sometimes have taken tylenol in addition to my pain meds which already contain acetaminophen. I just realized the max dose of acetaminophen is 4grams per day. I know I have taken 5 grams at times when I use tylenol in addition to my pain meds. Now that I now the danger to my liver I watch my medication intake very closely. However I am concerned that I may have damaged my liver? How do I know if that is the case?