OBJECTIVES: To study the cost of cancer pain management in the Maccabi database. This database delivers information on diagnosis, treatment and costs. Costs were compared for patients that were on MOR and switched to FEN and costs were assessed relative to total treatment cost. METHODS: A selection was made of all cancer patients (N=1,082) treated with strong opioids during 1997-1998. Fifty-two percent were women and average age 62 years. Fifteen percent of the patients had skin cancer and 10% was reported with lung cancer. Patients were divided in four different groups based upon the sequence of strong opioid use: FF is the group that was on FEN, MF was the group that started on MOR but switched to FEN, FM vice versa and MM were on MOR throughout. RESULTS: In the MF group significantly fewer infections and abdominal pain were reported when patients after switching to FEN. Also a reduction in drugs used was observed after switching to FEN: laxatives, H2-blockers, anti-emetics, anti-diarrhea, antibiotics, NSAIDs and other pain treatments. The total mean daily drug acquisition cost was 162 New Israelian Shekel (NIS) for the MOR period and 115 NIS while on FEN, a reduction resulting from reduced need for concomittant medication. The cost for pain management accounted for 3.1% (MM) to 6.7% (MF) of the total expenses, indicating the relatively low impact the choice of pain strategy has on total cost. CONCLUSION: This database analysis indicates that FEN treatment generates fewer costs compared to MOR treatment in patients switching from MOR to FEN. Without an adequate control group it is difficult to determine whether this reflects resource utilisation related to the selected pain treatment or changed medical practice in the course of cancer treatment. Overall the cost of pain management is low relative to the total cost for these patients.