Related Experiment Video
Updated: May 23, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
The alimentary absorption of diamorphine and morphine in man as indicated by urinary excretion studies
R G Twycross1, D E Fry, P D Wills
1St Christopher's Hospice, Lawrie Park Road, London.
Abstract:
1 Urine was collected over 24 h from 40 patients with advanced malignant disease who had received a known four-hourly oral dose of either diamorphine or morphine in an elixir or of diamorphine by injection for at least 3 days. 2 Samples were assayed for total urinary morphine (free and conjugated) by gas-liquid chromatography. 3 The percentage of the administered dose recovered as morphine was: (a) diamorphine hydrochloride by injection: 70% (s.d. 25) (b) diamorphine hydrochloride by mouth: 77% (s.d. 27) (c) morphine sulphate by mouth: 56% (s.d. 21) 4 It is suggested that diamorphine hydrochloride is completely absorbed by the gastro-intestinal tract but that morphine sulphate is only some two-thirds absorbed.
Related Concept Videos
Methods for Studying Drug Absorption: In situ
The Doluisio method involves perfusing a prepared segment of a rat's small intestine with a solution of radiolabeled drug and a non-absorbable marker. This helps to differentiate between absorbed and non-absorbed drug concentrations. The intestinal segment is connected at both ends using tubing and syringes,...
Opioid Analgesics: Synthetic and Semisynthetic Opioids
Methods for Studying Drug Absorption: In vitro
The diffusion cell method uses a two-compartment cell, including a donor compartment with the drug solution, which simulates the environment where the drug is applied, and a receptor compartment with a buffer solution, which simulates the environment...
Opioid Analgesics: Morphine and Other Natural Cogeners
Measurement of Bioavailability: Pharmacokinetic Methods
Drug Excretion: Miscellaneous Routes

