Background & Objectives: Opium addiction is a major social, psychological and health problem in the world. In past decades addiction to legal and illegal drugs has been widespread and over 1000 kinds of narcotics have been recognized, which are used in different ways including eating, smoking, injection and inhaling. Statistics published by international organizations such as UNDCP, WHO and UNSCO indicated an increasing trend in drug abuse worldwide. The countries are different only in the pattern of drug abuse. This study investigates the pattern of drug abuse in last 5 years in Ardabil.

  Methods : This is a descriptive, analytical and prospective study. To obtain the trend of substance abuse the records of all addicts in 1998 (684 cases) and 2002-2003 (341 cases) were studied. The collected data were analyzed by SPSS software (rel.11) using descriptive statistics.

  Results: The findings indicated that in the last five years the use of hashish, opium extract and other substances has decreased whereas the trend of heroin and opium use has increased. The use of opium has increased from 48.07% in 1998 to 67.4% in 2002-2003. Also the heroin use has increased from 8.5% in 1998 to 27.5% in 2002-2003. Moreover, the use of hashish, opium extract and other narcotics has decreased. The highest decrease (23.5%) belonged to opium extract and the highest increase (19%) to heroin.

  Conclusion : According to the results we could say that the pattern of substance abuse in Ardabil in the last five years has changed and heroin and opium consumption has increased.

  Background & Objectives : This study was prepared to determine the frequency of Staphylococus aureus nasal colonization among intravenous drug abusers with respect to this fact that the rate of colonization is dependent on various factor including addiction behaviours. There wasn't any native study on this subject. The purpose of this study was to prepare the basic data of S.aureus nasal colonization among intervenous drug abusers, in order to reducing the incidence and nasal carriage rates of S.aureus infections.

  Methods : This was a prospective cross sectional study that included all of intravenous drug abusers who referred to three hospitals of Tehran from 2005 to 2006. Specimens for culture were obtained by swabbing anterior nares. Swabs were inoculated into nasal chapman broth and incubated at 35 °C for 48 hours. Isolated colonies were further subjected to identification and antimicrobial susceptibility testing. The related data were collected using patients` medical files and analyzed with using SPSS 11.

  Results : Staphylococcus aureus was grown i n 38 cultures (26.2%). We did not find any significant relationship between variables such as, economic condition, methods of using drugs, frequency of drug use, infection with different viruses, gender and colonization by Staphylococcus aureus.

  Conclusion: We observed lower nasal colonization with Staphylococcus aureus among patients. We suggest preparing similar study in order to clarify the role of different factors that have effect on the rate of nasal colonization with Staphylococcus aureus.