It is commonly recognized than opioids analgesics have an major place in the treatment of pain. In spite of guidelines, opioids drugs remain underutilized in chronic cancer pain and acute severe pain. Among the possible factors, involved in the insufficient use of opioids drugs, is the fear (opiophoby) of physicians, nurses, patients and family to induce or to maintain an addiction. This review examines the potential of iatrogenic addiction. We will examined the place of morphine-like drugs in the treatment of severe acute pain and chronic cancer pain, the definition of dependency in pain patients, the assessment of the dependency potential in patients treated for pain. Available studies indicate that iatrogenic addiction is quite scarce and that the risk for a major tolerance is very small. Further studies will be necessary, since opioids analgesics may also be useful in some non-cancer chronic pain.