Just to close the loop on this part of the discussion - you have no clue what my medical background is, but it has nothing to do with Google searches.
The sad part is that we both err on the side of caution with meds. I've seen far too much damage that meds can do and docs are quick to add new meds but many (most) times won't say "now quit taking that other stuff".
Feel free to respond, but I won't take the bait.
If I knew someone was healthy, knew their liver and renal function was fine and had a full medical/social history, I wouldn't 100% be opposed to a higher dose, but I normally follow the advice of the nephrologists I've been lucky enough to work with and the guidance of the hospitals policies, rather than negotiated dosing guidelines between manufactures and the FDA. People take so much shit. Look at the studies coming out of Europe for the last decade on supplements and vitamins. Look at the shear number of OTC medications that people can buy and have literally no clue what the contraindications are. Take a trip to a few hospitals and look at the crazy number of renal and liver insufficient patients they're caring for. Tylenol is regarded as one of the most dangerous drugs in the world by some pretty well respected scientist and physicians. Am I claiming that it is? No, but there's merit to their arguments.
Do you know what supplements and vitamins anyone in this thread is taking? Do you know their hepatic and renal function? Do you know their medical history? Do you know their social history? If you can't honestly answer yes, then you probably shouldn't be telling them to take high doses of Tylenol.
You want to argue that, great, have at it, just don't pull the "you don't know my medical background" BS on me. There's no bait to take. I'm giving my opinion based on 30 years experience, if you have a different opinion based on actually being legally responsible for prescribing medications to people, I'm all ears. If you want to point out other providers have differing opinions, great, there's arguments to be had on either side of the issue. But that isn't what you did. You cut and pasted from the first google search to say that 4000mg a day is fine for someone that you have no idea what GNC supplement kick they're on. You don't have an argument, you cut and pasted from the first thing you found on google.