evaluation of opium effect on common bile duct diameter

background: narcotic addiction is one of the most important problems in human communities that unfortunately it's prevalence has been increased in our country inconveniently. opium has various effects on the parts of body. many studies has been performed about these effects, but opium effect on common bile duct has allocated only small quantity. materials and methods: this study is a cross-sectional study which carried out during 9 months (2004-2005). 50 opium addicts were selected from patients with non-ulcer dyspepsia who referred to fatemiye hospital with opium addiction. opium addiction was defined as daily use for at least 2 years. common bile duct diameter was measured by a sonographist. finally, mean of common bile duct diameter in both groups was calculated and the effect of opium consumption, duration and type of opiate on common bile duct was analyzed. results: mean of common bile duct diameter was obtained 4.1|â¡|1.8 mm in opium addicted group and 2.8|â¡|0.6 mm in control group. by considering p‹0.0001 in t-test and p=0.003 in mann-whitney test. there was significant difference between the common bile duct diameter in two groups. there is no difference between oral or inhalation route or type of opium in common bile duct diameter but by using the linear regression model the diameter increases 0.17 mm per 1 yr consumption (p‹0.0001). conclusion: the opium addicted persons have more dilated common bile duct than the normal population.