Age- and gender-specific acute poisoning with drugs and medications affecting nervous system.

Background: We investigated acute poisonings resulting from medications affecting the nervous system and illicit substances at Loghman Hakim Hospital in Tehran.

Methods: We retrospectively reviewed patient records at Iran's largest tertiary toxicology referral center between January 2010 and December 2015. We analyzed the prevalence, trend, age and gender distribution of acute poisoning caused by nervous system agents.

Results: The present study included 16,657 (57.27%) males and 12,426 (42.73%) females, resulting in 29,083 patients. The median age of men and women was 29 and 26 years, respectively (p < 0.0001). There were 12,071 (72.47%) men and 10,326 (83.10%) women under the age of 40 (p < 0.001). Most cases were intentional (69.38% in men and 79.00% in women, p < 0.001) and 44.10% had a history of poisoning. The proportions of men and women varied significantly between different age groups and nervous system agents. For women, the most common agent was alprazolam, whereas for men, methadone. The overall trend of acute poisoning with drug used in addictive disorders, opioids and alcohol was increasing but decreasing with benzodiazepines and antidepressants. Acute poisoning by nervous system agents led to more deaths in men (1.95% vs. 0.56%; p < 0.001).

Conclusions: Methadone intoxication was common especially among young men and most of these intoxications were intentional. Women and men aged 20-29 most frequently suffer poisoning from alprazolam and clonazepam, respectively. Women over 60 and men over 30 used opium. Illicit drugs caused more than half of the deaths, and opium dominated. This study may create awareness and develop educational and preventive gender and age-specific local programs.