The consumption of antidepressant drugs has increased in these last years, leading to severe and lethal poisonings. In this work, analytical tools, namely GC/MSD and GC/NPD/iμECD, were used to identify and quantify several antidepressant drugs including amitriptyline, imipramine, sertraline, fluoxetine, and citalopram in forensic cases in the North of Chile during 2008-2011. Drugs were analyzed in biological arrays like blood. A solid phase extraction by Bond Elut Certify columns was applied in all these processes. Fluoxetine and sertraline were derivatized with pentafluoropropionic anhydride. Prazepam was used as internal standard (IS). The limit of detection (LOD) in blood were 0.5 - 20.07 ng/mL. The average extraction rate was 89.39% in blood. The relative standard deviation (RSD) was less than 3.6%, while the intra-day accuracy was < 5.5% and the inter-day was < 2.4%, referred to RSD. The procedures we have developed allow the quantification of drugs even at low therapeutic doses, a very important issue taking into account the nature of the analyzed arrays.