A comparison of the effects of tramadol and morphine on gastric emptying in man

• Published in: Anaesthesia 1997-12, Vol.52 (12), p.1224-1229
• Main Authors: Murphy, D. B., Sutton, A., Prescott, L. F., Murphy, M. B.
• Format: Article
• Language: English
• Subjects: Absorption - drug effects; Acetaminophen - blood; Adult; Analgesics, Opioid - pharmacology; Analgesics; morphine, tramadol; Biological and medical sciences; Cross-Over Studies; Double-Blind Method; Drug toxicity and drugs side effects treatment; Electric Impedance; Gastric Emptying - drug effects; Gastrointestinal tract; gastric emptying; Humans; Measurement techniques; epigastric impedance, paracetamol absorption test; Medical sciences; Morphine - pharmacology; Pharmacology. Drug treatments; Toxicity: digestive system; Tramadol - pharmacology
• ISSN: 0003-2409; 1365-2044
• DOI: 10.1111/j.1365-2044.1997.214-az0349.x

In a previous study using an electrical bioimpedance technique and the paracetamol absorption test, we demonstrated that 0.09 mgkg−1 of morphine delayed gastric emptying in healthy human volunteers. The aim of this study was to investigate whether analgesic doses of tramadol would cause a delay in gastric emptying similar to conventional opioids. Using the same volunteers and techniques as in our previous study, placebo or tramadol (1 mgkg−1) was given in a randomised, double‐blinded, cross‐over placebo‐controlled study. Gastric emptying was measured concurrently by a noninvasive epigastric bioimpedance technique and by the paracetamol absorption test. After the ingestion of 500 ml of deionised water plus paracetamol 1.5 g, the mean (SEM) time taken for gastric volume to decrease to 50% (t0.5) was recorded. No difference in gastric emptying rates (t0.5) between placebo, 7.7 (1 min), and tramadol, 9.5 (2 min), was noted. In our previous study, morphine prolonged t0.5 to 21 (3) min (p