Tramadol 3-0-desmethyl

Musshoff et al. [35] developed a method for the enantiomeric separation of the synthetic opioid agonist tramadol and its desmethyl metabolite using a Chiralpak AD column containing amylose tris-(3,5-dimethylphenylcarbamate) as chiral selector and a n-hexane/ethanol, 97 3 v/v (5mM TEA) mobile phase nnder isocratic conditions (1 mL/min). After atmospheric pressure chemical ionization (APCI), detection was carried out in positive-ion MS-MS SRM mode. The method allowed the confirmation of diagnosis of overdose or intoxication as well as monitoring of patients compliance. 

Opioid receptor affinity Tramadol (Frink et al., 1996) itself has a weak opioid receptor affinity, the active metabolite O-desmethyl-tramadol has p-selectivity and p-affinity about 10 times lower than that of morphine. 

Analgesic efficacy and clinical use Tramadol HCI (Friderichs et al., 1978 Raffa and Friderichs, 1996) is a centrally-acting analgesic with a p-opioid and non-opioid component of action (Raffa et al., 1992). The non-opioid component induces inhibition of spinal pain transmission via inhibition of noradrenaline (NA) and serotonin (5HT) re-uptake (Driessen and Reimann, 1992 Driessen et al. 1993) Tramadol is a racemate and uptake inhibition and opioid properties are differentially distributed between the enantiomers (Raffa et al., 1993) and the active O-desmethyl metabolite. p-Opioid receptor binding, NA uptake inhibition and 5HT uptake inhibition are regarded as the relevant (Desmeules et al., 1996 Raffa and Friderichs, 1996) components of the complex analgesic action profile of the compound (+)-0-desmethyl-tramadol mainly contributes to p-activity, (-)-tramadol to NA uptake inhibition and (+)-tramadol to 5HT uptake inhibition, respectively. 

Pharmacokinetic properties Tramadol is extensively metabolized by O- and N-demethylation yielding the active metabolite O-desmethyl-tramadol (Ml) and several... 

Tramadol Decreased 0-desmethyl tramadol Slightly decreased analgesia and... 

Commercial stock standards Cis-tramadol HCl, O-desmethyl-cis-tramadol HCl, meperidine, fentanyl, norfentanyl, ( ) methadone, EDDP, all at 1.0 mg/mL, and normeperidine at 100 pg/mL (Cerilliant Corporation, Round Rock, TX). 

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