Aim: To investigate the potential pro-analgesic effect of the non-specific CCK antagonist proglumide on the analgesia produced by dihydrocodeine.
Method: A double-blind, placebo-controlled crossover study of 30 adult subjects.
Results: Mean pain scores fell from a baseline of 8.12–7.89 during the placebo phase (N.S.) and to 6.82 during the proglumide phase (P < 0.05). Side effects were minor.
Conclusion: The CCK antagonist proglumide enhances the analgesic effect of dihydrocodeine.
We have previously shown that the cholecystokinin (CCK) antagonist proglumide enhances the analgesic effect of sustained-release morphine in subjects with chronic pain of mixed etiology. 1 This peptide, represented in the central nervous system as well as the gut, 2 has an anti-opioid effect. 3 Levels of this peptide are increased after neural injury 4,5 and with chronic opiate administration. 6 Antagonism of these elevated levels in the animal model can enhance the analgesic effect of opiates. 7,8 The aim of this study was to examine if a CCK antagonist can enhance the analgesic effect of dihydrocodeine in human subjects.