IMHO any medicine powerful enough to do you much good is going to be powerful enough to do harm if misused.
I have found that Ibuprofen, 200mg, works better for me on joint pain better than any of the other common OTC pain relievers. Also seems to work well for tooth and sinus issues.
I have it on good authority that Acetaminophen can be very toxic to the liver. Chugging down a bottle of extra-strength is a common way of committing suicide. A difficult one to counter seeing as the liver dies and once gone the only option is a transplant. It is a slow, painful and messy way to die.
Related to this, don't use Acetaminophen, Tylenol, to treat a hangover. Alcohol is tough on the liver. Adding the toxic effects on the liver from Acetaminophen can be too much. Livers are tough, they are one of the few organs that can regenerate itself if you don't poison it too much, but there are limits.