From the Guidelines
Diphenoxylate acts as an agonist at mu (μ) opioid receptors, producing strong analgesia and other effects such as constipation, respiratory depression, and euphoria 1.
Mechanism of Action
- Diphenoxylate's action on mu opioid receptors results in analgesia mediated through brain mechanisms and spinal mechanisms 1.
- The effects of diphenoxylate on mu opioid receptors also include respiratory depression, which can be dose-dependent and lead to decreased responsiveness of ventilatory centers to carbon dioxide 1.
- Other effects of diphenoxylate's action on mu opioid receptors include constipation, due to delayed gastric emptying and peristalsis, and euphoria, which can contribute to its potential for abuse and addiction 1.
Clinical Considerations
- The use of diphenoxylate and other opioids requires careful consideration of the potential risks and benefits, including the risk of tolerance, physical dependence, and addiction 1.
- Diphenoxylate's narrow therapeutic index and wide interpatient range of necessary dose require careful dosing and monitoring to minimize adverse effects 1.
- As with other opioids, diphenoxylate should be used with caution in patients with a history of substance abuse or addiction, and alternative treatments should be considered when possible 1.
From the Research
Effect of Diphenoxylate on Mu (μ) Opioid Receptors
- Diphenoxylate is a mu (μ) receptor agonist, which has been shown to slow gastrointestinal transit by its effects on the circular and longitudinal muscle of the intestine 2.
- As a mu receptor agonist, diphenoxylate has a similar mechanism of action to other opioids, such as morphine, which act on mu opioid receptors to produce their therapeutic and side effects 3, 4, 5.
- The activation of mu opioid receptors by diphenoxylate can lead to various behavioral effects, including pain relief, dependence, and respiratory depression 5.
- The mu opioid receptor is a key target for the development of addiction therapies, and understanding its function is crucial for addressing the ongoing opioid epidemic 6.
Mechanism of Action
- Diphenoxylate acts on mu opioid receptors to produce its effects, which are mediated by the binding of the drug to the receptor and the subsequent activation of downstream signaling pathways 2, 4.
- The mu opioid receptor is a G protein-coupled receptor, and its activation by diphenoxylate leads to the inhibition of adenylate cyclase activity and the reduction of cAMP levels 4.
- The effects of diphenoxylate on mu opioid receptors can be influenced by various factors, including the drug's pharmacological efficacy, receptor selectivity, and pharmacokinetics 5.