[Prescription shopping of addictive drugs in Norway].

BACKGROUND: A Regular General Practitioner Scheme was introduced in Norway in 2001. One aim was to restrict patients from "shopping" doctors and prescription drugs.

MATERIAL AND METHODS: Data from The Norwegian Prescription Database (NorPD) for 2004 were used to assess the following: number of physicians each patient had used to obtain prescriptions for a drug, the relationship between number of physicians used and amount of drugs prescribed, and concomitant prescription of opioids and benzodiazepines during the same period to the same patients. The drugs studied were the prescription drugs with potential for abuse; diazepam, carisoprodol and codeine combinations. The information retrieved was compared to that for the supposedly non-addictive drugs esomeprazole, metformine and salbutamol.

RESULTS: More than 96 % (96.3 - 98.9) of the patients used one or two physicians for prescriptions of the same drug, and fewer than 0.5 % (0.01 - 0.26) used five or more physicians. However, the proportion of patients who used five or more physicians for the addictive drugs was 9.5 times higher than that for a comparable proportion of patients using the non-addictive drugs. The amount of dispensed drug increased considerably more with the number of physicians used for addictive drugs than for non-addictive drugs, as did the amount of concomitantly dispensed opioids and benzodiazepines.

INTERPRETATION: The occurrence of prescription drug shopping in the Norwegian population was limited. Among the few patients who used many physicians for prescription of drugs, the phenomenon was much more frequent for users of addictive drugs than for users of the non-addictive drugs. The study suggests that prescription drug shopping may be an indicator of a drug abuse potential.