What does the 3 stand for in Tylenol 3 with codeine?

The "3" in Tylenol 3 refers to the amount of codeine contained in the medication, which is 30 mg. Tylenol 3 combines acetaminophen (300 mg) with codeine to provide pain relief. The medication is typically prescribed for moderate pain and is part of a series that includes Tylenol 1 and Tylenol 2, which contain lower doses of codeine.