Background: Professional neglect is a civil responsibility for any specialist or individual with a specific skill, including therapists, and is not limited to any particular profession. Case Presentation: A man 41-year-old drug abuser was diagnosed with a heart problem due to methamphetamine abuse. Despite his drug history, he was once admitted to the emergency room for chest pain, where acetaminophen and diazepam were prescribed. For the second time, he went to another medical center due to continued chest pain, and due to the suspicion of contracting COVID-19, a CT scan of the chest was performed, yielding negative results, and then he was discharged. The patient was found deceased in his bed the following day. An autopsy revealed a thinned heart wall, subendocardial hemorrhages, and severe atherosclerosis. Methamphetamine, amphetamine, and acetaminophen were detected in urine samples, and ethanol was detected in blood and vitreous humor samples. Conclusion: The case highlights the importance of medical negligence in treating patients with drug abuse.