This study assessed the occurrence of nine pharmaceuticals (caffeine, ibuprofen, metronidazole, ciprofloxacin, amoxicillin, chloramphenicol, diclofenac, doxycycline, and paracetamol) in leachate and soil samples from eight dumpsites within the Ejisu-Juaben Municipality in the Ashanti Region of Ghana. It evaluated the ecotoxicological risk posed by these pharmaceuticals to organisms. The study also investigated the disposal patterns of pharmaceuticals by inhabitants of the municipality. After solid-phase extraction, the residues of selected antibiotics and analgesics in soil and leachate samples were analyzed using an HPLC–PDA method. Five of the pharmaceuticals were detected in the leachate and soil samples. Chloramphenicol, diclofenac, and paracetamol were detected in all leachate and soil samples, with concentrations ranging from 0.01 to 74.53 µg/L in leachate and 0.06–305.06 µg/kg in soil samples. Chloramphenicol had the highest concentration in leachate samples, while amoxicillin had the highest concentration in soil samples. Ecological risk assessment indicated that even the least detected pharmaceuticals posed a significant risk to fish, daphnia, and algae, with hazard quotients ranging from 0.56 to 1742.75. Survey results indicated that 71.0% of respondents disposed of unwanted or expired medicines. Within this group, 83.5% inappropriately disposed of expired drugs by placing them in household garbage, which is destined for dumpsites. Additionally, 52% of respondents wanted to protect the environment and would willingly contribute financially to enhance remediation efforts. The findings emphasize the urgent need for environmental policies and public education on proper pharmaceutical disposal to mitigate the ecological risks posed by pharmaceutical contaminants in developing regions. Altogether, the study highlights the presence of pharmaceutical residues in dumpsites at levels that could harm the ecosystem's health. Continuous monitoring and strategies to reduce pharmaceutical release into the environment are essential to protect the environment.