Abstract: Process for determination of a drug or medicament or their metabolites in a (body) fluid or an extract of (body) tissue or (body) sample comprising the steps: (i) optionally treatment of the fluid or sample extract with at least one enzyme, (ii) contacting at least a first part of the fluid or extract with at least one first solid phase able to adsorb or absorb organic compounds out of the fluid or extract, and/or (iii) contacting at least a second part of the fluid or extract with at least one second phase, able to extract or adsorb organic compounds out of the fluid or extract, and/or (iv) optionally contacting at least a third part of the fluid or extract with a liquid phase able to extract organic compounds out of the fluid or extract, and/or (v) desorbing the compound(s) bound to the first solid phase by applying heat to the solid phase and/or by solvent extraction, optionally followed by evaporating the solvent at least partially, (vi) optionally extracting or desorbing the compound(s) contained in or b