Enantioselective analysis of unbound tramadol, O-desmethyltramadol and N-desmethyltramadol in plasma by ultrafiltration and LC–MS/MS: Application to clinical pharmacokinetics

Effects of type 1 and type 2 diabetes on the pharmacokinetics of tramadol enantiomers in patients with neuropathic pain phenotyped as cytochrome P450 2D6 extensive metabolizers

“…Total concentration of tramadol, M1 and M2 enantiomers were analysed by HPLC coupled with tandem mass spectrometry, as described previously by our research group [18]. In summary, 500‐μl plasma aliquots were spiked with 25 μl of the solution of internal standard (100 ng/ml verapamil), and the analytes were extracted using methyl‐tert‐butyl ether in alkaline medium.…”

“…Binding to plasma proteins of tramadol and its metabolites is not enantioselective. The plasma protein binding is approximately 40% for both tramadol enantiomers, >80% for M1 enantiomers and 75–80% for M2 enantiomers [18]. An experimental study reported that rats with streptozotocin‐induced diabetes presented higher plasma concentrations of both tramadol and its M1 metabolite when compared with nondiabetics, suggesting induction of the metabolism or impaired renal elimination resulting in increased exposure [19,20].…”

Simultaneous Determination of Paracetamol and Tramadol in Pharmaceutical Tablets by Derivative UV-Vis Absorption Spectrophotometry

“…Liquid chromatography (LC) was used to determine tramadol in combination with Aceclofenac in a commercial tablet [27]. Ultrafiltration and LC-MS/MS in combination of Odesmehtyltramadol and N-desmethyltramadol in plasma [28], by Meta-analysis [29], and by GC-MS in human urine [30].…”

Intracerebral microdialysis coupled to LC–MS/MS for the determination tramadol and its major pharmacologically active metabolite O‐desmethyltramadol in rat brain microdialysates

“…[5] To obtain analgesia without side effects, it is important in clinical practice and animal experiments to adjust the safe and effective concentration of tramadol and ODT. [11][12][13] Some of these techniques were applied to biological samples such as brain tissue, [14][15][16][17][18][19] saliva, [20] urine, [20][21][22][23][24][25] amniotic fluid, [26] and plasma. [11][12][13] Some of these techniques were applied to biological samples such as brain tissue, [14][15][16][17][18][19] saliva, [20] urine, [20][21][22][23][24][25] amniotic fluid, [26] and plasma.…”