RT Book, Section
A1 Smollin, Craig
A2 Papadakis, Maxine A.
A2 McPhee, Stephen J.
A2 Rabow, Michael W.
A2 McQuaid, Kenneth R.
SR Print(0)
ID 1193161495
T1 Acetaminophen Overdose
T2 Current Medical Diagnosis & Treatment 2023
YR 2023
FD 2023
PB McGraw-Hill Education
PP New York, NY
SN 9781264687343
LK accessmedicine.mhmedical.com/content.aspx?aid=1193161495
RD 2024/04/20
AB Acetaminophen  (paracetamol  in  the  United  Kingdom,  Europe)  is  a  common  analgesic  found  in  many  nonprescription  and  prescription  products.  After  absorption,  it  is  metabolized  mainly  by  glucuronidation  and  sulfation,  with  a  small  fraction  metabolized  via  the  P450  mixed-function  oxidase  system  (2E1)  to  a  highly  toxic  reactive  intermediate.  This  toxic  intermediate  is  normally  detoxified  by  cellular  glutathione.  With  acute  acetaminophen  overdose  (greater  than  150–200  mg/kg,  or  8–10  g  in  an  average  adult),  hepatocellular  glutathione  is  depleted  and  the  reactive  intermediate  attacks  other  cell  proteins,  causing  necrosis.  Patients  with  enhanced  P450  2E1  activity,  such  as  patients  who  have  alcohol  use  disorder  and  patients  taking  INH,  are  at  increased  risk  for  developing  hepatotoxicity.  Hepatic  toxicity  may  also  occur  after  overuse  of  acetaminophen—eg,  as  a  result  of  taking  two  or  three  acetaminophen-containing  products  concurrently  or  exceeding  the  recommended  maximum  dose  of  4  g/day  for  several  days.  The  amount  of  acetaminophen  in  US  oral  prescription  combination  products  (eg,  hydrocodone/acetaminophen)  is  limited  by  the  FDA  to  no  more  than  325  mg  per  tablet.