“…Since both tobacco and opioid analgesics are dependent substances that activate the brain reward system, the use of opioid analgesics in current or former smokers is often a topic of scientific discussions. Previous reports indicated that smokers had more high risk for prevalence rates of opioid analgesic use [ 120 – 122 ], opioid analgesic use consumption [ 84 , 111 , 123 , 124 ], and opioid use disorders [ 104 , 122 , 124 , 125 ], compared with nonsmokers.…”