The same box says 3,000 mg and 4,000 mg a day, and both are right
Tylenol Extra Strength's directions allow 6 caplets of 500 mg, or 3,000 mg. The liver warning on the same label names 4,000 mg, counting every acetaminophen source together.
What the study found
One Tylenol label carries two different daily maximums
Tylenol Extra Strength's directions allow 6 caplets of 500 mg in 24 hours, or 3,000 mg of acetaminophen. The liver warning on the same label names 4,000 mg in 24 hours. The lower is the maker's own voluntary ceiling for that product; the higher counts every acetaminophen source combined.
The caveat · Neither is where injury begins
Neither number marks a point where injury begins, and reading either as one is the most common mistake made with this drug. This is one product from one manufacturer in one country: other acetaminophen products, Tylenol's own included, print different strengths and different ceilings, and labels outside the United States differ again. The two figures also count differently, one per product and one across everything taken, which is exactly what makes them easy to swap.