The Sound of Evolution
Diphenoxylate
Mechanism of action:
Diphenoxylate is an opioid and a piperidine derivative. It is a partial agonist of the μ-opioid receptor and acts mainly on the enteric nervous system. Its central nervous system effects are relatively weak at usual therapeutic doses, although overdose may still produce reactions related to central nervous system depression. When diphenoxylate activates μ receptors in the intestinal wall, it inhibits neurons from releasing acetylcholine, reducing intestinal motility and intestinal fluid secretion. This lowers stool water content and promotes stool formation, thereby reducing diarrhea.
Reference(s):
1. Chen X et al. (2002). TTD: Therapeutic Target Database. Nucleic Acids Res.
2. Baker DE et al. (2007). Loperamide: a pharmacological review. Rev Gastroenterol Disord.
3. Corazziari E et al. (1999). Role of opioid ligands in the irritable bowel syndrome. Can J Gastroenterol.