Background/aims: The aim of this study is to prove that an early conversion from oral morphine to transdermal fentanyl is an effective and safe treatment modality for patients with cancer pain.
Methodology: Early conversion to transdermal fentanyl was evaluated for patients with cancer pain (VAS > or = 4) by administering 20-30 mg of morphine.
Results: The early conversion to transdermal fentanyl improved cancer pain in comparison to oral morphine. The mean VAS score improved to 2.6 +/- 2.8 after treatment, whereas the mean VAS score was 5.67 +/- 2.4 before treatment by transdermal fentanyl. Eighteen of 24 patients (75%) were responders due to an early conversion by the VAS score, and the mean VAS score after transdermal fentanyl was 1.2 +/- 0.9 in responders. Finally, 66.7% of all patients received from 2.5 mg to 5.0 mg of transdermal fentanyl. The VAS score before conversion from oral morphine to transdermal fentanyl showed a significant difference (responder vs. non-responder: 4.7 +/- 1.8 vs. 8.5 +/- 1.4, P<0.001). Rescue treatment for cancer pain was required for 16 series in 13 patients. Vomiting, nausea, constipation, and drowsiness were observed as adverse effects. However, the nausea symptoms significantly improved after treatment with transdermal fentanyl (P<0.05).
Conclusions: Early conversion from oral morphine to transdermal fentanyl helped to effectively relieve cancer pain while improving the effects of morphine induced nausea.