OBJECTIVES: prevalence of heroin addiction among Italian population aged 15-64 is 0.8%. Three different drugs are currently available for treating heroin addiction: methadone, buprenorphine and buprenorphine/naloxone. A monocenter, retrospective, one-year follow-up cost-utility analysis (CUA) was performed to compare buprenorphine/naloxone (211 patients) vs buprenorphine (214 patients) and methadone (512 patients) for heroin addiction detoxification at Department of Addictions, Local Health Authority of Varese, Italy. METHODS: CUA adopted the Department of Addictions viewpoint. Clinical, economic and utility data were obtained from the database of the Department of Addictions and literature. Drugs, bottles for methadone take-home doses, health care and social services were identified, quantified and valued in Euro (€) 2009. One-way and probabilistic sensitivity analyses (SAs) were performed. RESULTS: 87.8% of patients are male. Mean (±standard deviation) patients’ age is 37.9±7.2 years, whereas patients’ first contact with heroin dates back to 16.7±8.5 years. Neither heterogeneity nor sample selection bias have been detected among treatment groups. Buprenorphine and methadone are the most and the least costly options (€3257.24 and €2219.47 per patient, respectively). Buprenorphine/naloxone costs €2541.05 per patient. During one-year follow-up patients accrue 0.573 (methadone), 0.599 (buprenorphine) and 0.602 (buprenorphine/naloxone) Quality-Adjusted Life Years (QALYs). Buprenorphine is strongly dominated by buprenorphine/naloxone and hence ruled out from the base case CUA. The incremental cost-utility ratio for buprenorphine/naloxone vs methadone is €11,195.12. SAs confirm the robustness of the base case findings. Cost-Effectiveness Acceptability Curve shows that the probability for buprenorphine/naloxone to be cost-effective equals 0.58, 0.61 and 0.62 against €25,000, €40,000 and €50,000 threshold-values, respectively. Cost-Effectiveness Acceptability Frontier highlights that buprenorphine/naloxone is the optimal alternative from a threshold-value of €11,391.14. CONCLUSIONS: Buprenorphine/naloxone seems advisable even from an economic point of view, since its incremental cost-utility ratio falls well within the usual acceptability standards for incremental QALY saved (€25,000-40,000; €50,000).