Posted on: June 26, 2009 6:02 PM, by Abel Pharmboy
Death of Michael Jackson: How could Demerol (meperidine) cause cardiac arrest?
Jackson apparently received IM meperidine injections, the TMZ report quoting a family member suggests they were given daily , a point that may be very telling: while meperidine itself has a relatively short half-life of 3 hr, the active CNS-stimulating metabolite normeperidine has a half-life of 15 to 20 hours. Therefore, daily IM injections over time might have caused normeperidine concentrations to accumulate to toxic levels relative to the parent drug.
Most relevant is that meperidine is metabolized ( N-demethylation by CYP2D6) to an active compound, normeperidine, which has been associated with paradoxical stimulation (not depression) of the central nervous system. This CNS stimulation has been linked to known reports of meperidine-induced seizures and is correlated directly with blood concentrations of the normeperidine metabolite that meperidine should be used extremely carefully with any CNS depressant. Concomitant use of other CNS depressants by Mr Jackson might be likely and these combination effects might also lead to the same end result of cardiac arrest
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YZ 1.Vital sign (&7;5 15 4 L1&G+ E8&+X5&G (&7;5 1 %*. 3 L1&G+ 2. 12(&+I4X5751EIAX E5(&7 respiratory rate J7@@4I5(K 12 L1&G+/ L(1 :)X 1. Severe respiratory depression: naloxone 2 mg (A>7j5 0.01 mg/kg) slow IV E5 CV@6W(I451J*K7 ?:GT*19AE@IbGN;5 2-3 1(*J*K>5D 10 mg 2. Mild respiratory depression: naloxone 0.4 mg slow IV 3 References: Drug Information handbook. 17 th edition page 997-999 Intraveneous medication 2004 page 727-730 AFHS 2003 page 2038-2040 4