Lortab, Norco, and Vicodin are Hydrocodone mixed with Acetaminophen. Like they said above, without the Acetaminophen, it is considered class 2. It's also added to keep you from overtaking the Lortab (the part that is Hydrocodone) I was told the highest amt. of Acetaminophen in a 24 hr period without causing liver or kidney toxicity is 3000mg. 4000mg if using on a short term basis. I was on Norco 10/750, taking 1 to 2 tabs every 4 to 6 hours. That was to much Acetaminophen. Now down to 10/350's at 5/day. I might see if my doctor will change to the Lortab.