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The mobile phase consisted of 10 mM potassium dihydrogen phosphate buffer\/methanol (87.5:12.5 v\/v), at a flow rate 1 mL\/min. Detection was set at 274 nm. The LOQ for all the compounds ranged from 14 to 41 ng\/mL. Excellent linearity was achieved over the studied range of concentration with correlation coefficients 0.9991\u20130.9998 (<jats:italic>n<\/jats:italic> = 6). The developed method was validated by precision and accuracy with RSD &lt;2.55%. On extraction of the drugs and metabolites from the urine samples high recoveries were achieved ranging from 82.06 to 98.34% w\/w on RP18 cartridges and methanol\/chloroform (20:80 v\/v) as the extraction solvent. 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