I'm prescribe oxycodone 5 mg by 325 2 every 4 hours total of 12 a day.. is this a dangerous amount of tylenol (acetaminophen)?

Yes: That is almost 4 grams of tylenol (acetaminophen) per day. This can cause liver damage. If you need that much narcotic, going to a sustained release medication without tylenol (acetaminophen) would be advisable.

Depending : On your weight. For adult person 325mg not a dangerous dose.But better take the medicine , when you really need it.

Near the maximum: It should be prescribed as needed. If you can get by with less it would be safer. Talk with your doctor and see what they can do to reduce the amount of tylenol (acetaminophen). Maximum is 4000 mg per day but it is recommended to stay below 3000 mg per day.

Tylenol (acetaminophen) and liver: These are general recommendations :the general recommended is you take a maximum of 4000 mg of Acetaminophen in 24 hours . If you take 12 of the pills you're taking 3900 mg. That does not mean that this is safe for you. More information is needed about your general health ; your liver, what other drugs you take if any.