Related Experiment Video
Updated: Aug 16, 2026

Fentanyl Analog Screening using LC-TIMS-TOF MS/MS
Published on: November 8, 2024
Rapid switching between transdermal fentanyl and methadone in cancer patients
Sebastiano Mercadante1, Patrizia Ferrera, Patrizia Villari
1Anesthesia and Intensive Care Unit, La Maddalena Cancer Center, Via San Lorenzo 312, 90146 Palermo, Italy. terapiadeldolore@la-maddalena.it
Purpose:
The aim of this study was to examine the clinical effects of switching from transdermal (TTS) fentanyl to methadone, or vice versa, in patients with a poor response to the previous opioid.
Patients And Methods:
A prospective study was carried out on 31 patients who switched from TTS fentanyl to oral methadone, or vice versa, because of poor opioid response. A fixed conversion ratio of fentanyl to methadone of 1:20 was started and assisted by rescue doses of opioids, and then doses were changed according to clinical response. Pain and symptom intensity, expressed as distress score, were recorded before switching doses of the two opioids and after subsequent doses. The number of changes of the daily doses, time to achieve stabilization, and hospital stay were also recorded.
Results:
Eighteen patients were switched from TTS fentanyl to methadone, and seven patients were switched from methadone to TTS fentanyl. A significant decrease in pain and symptom intensity, expressed as symptom distress score, was found within 24 hours after switching took place in both directions. Unsuccessful switching occurred in six patients, who were subsequently treated with an alternative therapy.
Conclusion:
A rapid switching using an initial fixed ratio of fentanyl to methadone of 1:20 is an effective method to improve the balance between analgesia and adverse effects in cancer patients with poor response to the previous opioid. No relationship between the final opioid dose and the dose of the previous opioid has been found.
More Related Videos
10:17High-throughput and Comprehensive Drug Surveillance Using Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry
Published on: April 23, 2019
09:54Combining Laser Capture Microdissection and Microfluidic qPCR to Analyze Transcriptional Profiles of Single Cells: A Systems Biology Approach to Opioid Dependence
Published on: March 8, 2020
Related Concept Videos
Opioid Analgesics: Synthetic and Semisynthetic Opioids
Transdermal Drug Delivery Systems
Chemotherapy-Induced Nausea and Vomiting: Cannabinoids
Two synthetic agonists of THC,...
Drug Delivery: Miscellaneous Routes
Oral inhalation and nasal sprays swiftly transfer drugs across the respiratory epithelium's mucosal layer. Inhaled glucocorticoids and bronchodilators directly target lung conditions such as asthma, while fluticasone nasal spray mitigates allergic rhinitis.
Transdermal patches transport drugs through the...
Therapeutic Drug Monitoring: Affecting Factors
Analgesia and Pain Management