31 Oct IV Melatonin Did Not Reduce Surgical Pain
Medical Research: What is the background for this study?
Dr. Andersen: The sleep hormone, melatonin is diverse molecule. Several experimental animal studies have documented significant antinociceptive effects in a wide range of pain models. In perioperative medicine, administration of melatonin has demonstrated anxiolytic, analgesic and anti-oxidant effects. Optimization of the analgesic treatment in surgical patients is required due to documented inadequate analgesia and the risk of adverse effects and complications caused by commonly used NSAIDs and opioids. Our goal was to investigate if melatonin was able to reduce pain scores or analgesic use in patients undergoing laparoscopic cholecystectomy.
Medical Research: What are the main findings?
Dr. Andersen: We were unfortunately not able to document any effects of 10 mg intravenous melatonin with respect to pain outcomes.
Medical Research: What should clinicians and patients take away from your report?
Dr. Andersen: Melatonin should be investigated further for two main reasons:
- it is without any serious adverse effects (opposed to other analgesics), and
- several animals and some human studies have previously demonstrated the analgesic effect.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Andersen: The analgesic effect of melatonin should be investigated in surgical procedures with a high postoperative pain-load in high–quality randomized pain trials. Pain measurement methods should be optimized, e.g. by incorporating activity-related pain and sufficient number of measurements, when pain is most intense.
Furthermore, future research should focus on optimal administration routes, timing of administration and dosage. Dosage is for example empirically chosen at this moment, and animal studies have administered up to 300 mg/kg melatonin, when documenting analgesic effects.
Absence of analgesic effect of intravenous melatonin administration during daytime after laparoscopic cholecystectomy: a randomized trial
Lars Peter Holst Andersen, MD, PhD (Fellow) Bülent Kücükakin, PhD (Resident), Mads U. Werner, DSc (Associate Professor), Jacob Rosenberg, DSc (Professor), Ismail Gögenur, DSc (Professor)
Journal of Clinical Anesthesia Published Online: October 28, 2014