Hot topics in opioid pharmacology: mixed and biased opioids.

@article{Azzam2019HotTI,
  title={Hot topics in opioid pharmacology: mixed and biased opioids.},
  author={Ammar A H Azzam and John McDonald and David G Lambert},
  journal={British journal of anaesthesia},
  year={2019},
  volume={122 6},
  pages={
          e136-e145
        }
}
Analgesic design and evaluation have been driven by the desire to create high-affinity high-selectivity mu (μ)-opioid peptide (MOP) receptor agonists. Such ligands are the mainstay of current clinical practice, and include morphine and fentanyl. Advances in this sphere have come from designing pharmacokinetic advantage, as in rapid metabolism for remifentanil. These produce analgesia, but also the adverse-effect profile that currently defines this drug class: ventilatory depression, tolerance… 
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