Opioid treatment of painful chronic pancreatitis.

Background: Abdominal pain is the dominant symptom in 50-75% of patients with chronic pancreatitis, often requiring opioid analgesics. Fentanyl, a potent synthetic opioid, can be administered percutaneously at a constant dose and is claimed to have fewer systemic side effects.

Aim: To evaluate transdermal fentanyl plaster versus sustained release morphine tablets as analgesic treatment of painful chronic pancreatitis.

Methods: In an open randomized crossover trial, 18 patients were included. The treatment period was 4 wk for each drug. All patients had immediate-release morphine tablets as rescue medication.

Results: The dosage of transdermal fentanyl had to be increased on average 50% over that indicated by the manufacturer. When this was done and rescue medication was secured, no difference between the two drugs in primary endpoint or patient preference was observed. There was also no difference in the secondary endpoints, pain control, and quality of life. However, skin side effects, mostly mild, occurred in 44% of the patients during treatment with transdermal fentanyl, and the mean daily dose of immediate release morphine was significantly higher during the transdermal fentanyl period than during the sustained-release morphine period (30.7 mg vs. 14.7 mg [p < 0.01]).

Conclusion: When given in an appropriate dose, transdermal fentanyl might be useful for treatment of some patients with painful chronic pancreatitis, e.g., when tablet ingestion is difficult. However, the dosage often has to be increased above that recommended by the manufacturer. The need of rescue morphine is considerable and skin side effects often occur. Transdermal fentanyl is, therefore, not the ideal first-choice analgesic in patients with painful chronic pancreatitis.