1. Opioid Metabolites Journal of Pain and Symptom Management
Jörn Lötsch, MD, PhD 
Journal of Pain and Symptom Management 
Volume 29, Issue 5, Pages (May 2005)
DOI: /j.jpainsymman
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

2. Fig. 1
Metabolism of tilidine, tramadol and meperidine into their active metabolites. The dotted frames show where the metabolic reaction takes place.
Journal of Pain and Symptom Management  , 10-24DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

3. Fig. 2
Glucuronidation of opioids occurs only on free hydroxy groups. Therefore, morphine is metabolized into two glucuronides whereas hydromorphone is only metabolized into a 3-glucuronide (top). The glucuronidation of morphine is shown at the bottom.
Journal of Pain and Symptom Management  , 10-24DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

4. Fig. 3 Metabolism of codeine and morphine metabolism.
Journal of Pain and Symptom Management  , 10-24DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

5. Fig. 4 Metabolism of dihydrocodeine.
Journal of Pain and Symptom Management  , 10-24DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions

6. Fig. 5
Time course of pupil diameter and tolerance to electrical pain stimuli after administration of morphine (IV-infusion of up to 6.4 hours) to healthy volunteers.48 The contribution of M6G is given as dotted lines. This estimate bases on data obtained after administration of M6G at a separate study. These data were fitted to PK/PD model for pupil size and pain. The resulting models and parameter values were then used together with the M6G plasma concentrations after morphine administration to calculate the M6G-related time courses of pupil size and pain tolerance.
Journal of Pain and Symptom Management  , 10-24DOI: ( /j.jpainsymman )
Copyright © 2005 U.S. Cancer Pain Relief Committee Terms and Conditions