Treatments for acute poisoning need an accurate diagnosis in a timely manner. In order to improve the diagnosis of acute lethal poisoning and consequently speedup the treatment, we need to identify the possible gaps and symptoms that lead to rapid diagnosis. To achieve this, we have analyzed medical records of hospitalized poisoned patients and their autopsy records after the corresponding patients are deceased. In this talk, we evaluate the consistency between these two data sets and highlight steps that can be taken for early life-saving treatments. The analysis is done by comparing clinical symptoms of the poisoned deceased patients through autopsy and toxicology at Tehran’s Medico-Legal Organization. The comprehensive examination includes all 98 admitted(deceased poisoned) patients at Baharloo Hospital during year 2014-2015. The deceased patients were then referred to the Kahrizak Autopsy Hall. Their hospital medical records and autopsy results are collected and compared via SPSS16. The cause of poisoning are, in order: 1)drugs(49%), 2)pesticides(39%) and 3)alcohol(1%). The most common cause of drug poisoning was found to be opioids. The hospital records and autops y results have the highest overlap in determining the cause of death intermofrice tablet(39%) and high-dose opioid poisoning(26%). Cohen’s Kappa coefficient is used as the evaluation measure to address the consistency between patient diagnoses based on hospital records and autopsy results. The estimated Cohen’s Kappa coefficient is 0.74 indicating a desirable rate of agreement. Keywords: Poisoning, Opium poisoning, Clinical diagnosis, Autopsy, Cohen’s Kappa coefficient