Caffeine, a mild central nervous system (CNS) stimulant present in coffee beans, cocoa beans, and tea leaves, can pose a threat in significant quantities, leading to severe health complications like arrhythmia, tachycardia vomiting, convulsions, coma, and, in extreme cases, death. We present a case involving the tragic demise of a young woman who took her own life by consuming a sleepiness-preventing medication purchased online, containing caffeine. The autopsy revealed pulmonary edema, congestion, and cutaneous emphysema. The stomach contents included a dark-brown viscous fluid with remnants of tablets and food. Toxicological analysis indicated elevated caffeine levels in various body tissues: femoral blood (195 mg/L), brain (115 µg/g), lung (293 mg/g), liver (202 mg/g), spleen (692 mg/g), kidney (288 µg/g), gall bladder (bile juice) (1500 µg/g), skeletal muscle (163 µg/g), small intestine (236 µg/g), and myocardial muscle (682 µg/g). Due to the presence of caffeine tablets in the stomach, the concentration was exceptionally high and therefore not quantified. The highest concentration of caffeine was found in the bile (1500 µg/g). The gas chromatography mass spectrometry (GC/MS) method used was validated according to the GTFCh guidelines. This case emphasizes the importance of caution and highlights the study's recommendation to address the toxicity risks associated with substances containing high caffeine concentrations. The suggestion is to include caffeine concentration assessments in routine forensic toxicological tests for all cases. In this case the cause of death was determined to be caffeine intoxication, with no trace of ethyl alcohol, drugs, pesticides hydrocarbons, or organic solvents detected in the body samples.