Pharmacogenetics describes the relationship between genetic variations and drug response. Variations occur in genes that code for components of the metabolic pathways and transport of the drug across the blood–brain barrier (affecting pharmacokinetic behavior) and in genes that code for the opioid receptor or proteins in downstream signaling pathways (affecting pharmacodynamic behavior) (Table 19-2: Examples of Pharmacogenetic Variations that Influence Opioid Analgesia).

Opioids

1. Short History
2. The Endogenous Opioid System
3. Opioid Receptor Knockout Mice
4. Classification of Exogneous Opioids
5. Opioids Acting at Opioid and Nonopioid Receptors
6. Opioid Mechanisms
7. Routes of Administration
8. Pharmcokinetics (PK) and Pharmacodynamics (PD)
9. PKPD Models for Opioid Effect: which End Point Serves the Clinician Best?
10. Pharmacodynamics: Dose Effect on Pain Relief
11. Pharmacogenetics
12. Opioid-Induced Respiratory Depression
13. Other Opioid-Related Side Effects
14. Remifentanil for Obstetric Labor Pain
15. Gender Differences