prescribers themselves and saying stop prescribing it. we don't think it offers any additional benefit and it could potentially cause some harm. >> how much is in like a tylenol? how much is in other products that people might be taking? do you know? >> well, there's regular strength, there's extra strength tylenol. and again, keep in mind we're talk about prescription medications. but for over-the-counter tylenol could be 250 milligrams, 500. some even are a full gram of tylenol. the magic number i will tell you they say if you're taking over 4 grams of acetaminophen in a day, that could just be a few extra strength tylenols, they say that's too much. that could potentially cause problems, serious problems with your liver, causing the liver to actually start to fail and requiring more drastic medical measures. >> i mean, a lot of people though take products with acetaminophen without even thinking there might be consequences after a night of drinking to prevent a hangover. is that something bad or somebody who has a shoulder -- i just had shoulder surgery and i've been taking one or two a day just to kind of deal with the pain. is that bad?