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Short answer What to know about injected acetaminophen Common questions Related questions Sources**If you are a healthy adult, most acetaminophen from an injection clears from your bloodstream within about 12 hours after your last dose.**
This estimate comes from an average adult half-life of 2.4 hours, meaning your body removes about half the remaining drug in that time. Your liver breaks it down, and your kidneys remove the breakdown products in urine. Your clearance can take longer with liver disease, and severe kidney disease can affect removal. Your dosing schedule is separate from clearance time, so follow your clinician's instructions and count acetaminophen in all your medicines.
What to know about injected acetaminophen
Common questions
How long does Acetaminophen Injection stay in your system?
If you are a healthy adult, most acetaminophen from an injection clears from your bloodstream within about 12 hours after your last dose. This estimate uses its average adult half-life of 2.4 hours; it does not mean every trace is gone. Your liver breaks down the drug, and your kidneys remove its breakdown products. Liver disease can prolong clearance. Doses are usually given every 4 to 6 hours, so clearance time does not tell you when to take more. Ask your clinician when you can take oral acetaminophen, and include your injection in your daily total.