PAIN-OPIOID SIDE EFFECTS

SUMMARY

1. Common side-effects: respiratory depression, constipation.

2. Pain-opioid downhill spiral: long-term side effect characterized by loss of functional capacity and depression.

3. Transient cognitive and psychomotor impairment during dose escalation and in opioid-naive patients.

4. Endocrine effects include decreased testosterone, progesterone, and estradiol (decreased libido in men and women); amenorrhea; and reduced cortisol response to stress. These effects are more common with administration of intraspinal opioids.

5. Hyperalgesia & pronociceptive effects of chronic opioid therapy mediated by the NMDA receptor cascade leading to a sensitization process. Periodic opioid rotation and the use of NMDA receptor antagonists (methadone, propoxyphene) can prevent this.

6. Tolerance: also mediated by NMDA receptor cascade.

7. Addiction & dependence.

OTHER ISSUES
8. Associated benzodiazepine use was found to be associated with functional impairment, increased health care use, depression, and pain.

Reference(s)

Cifu, D.X. (2020). Braddom’s physical medicine and rehabilitation. Elsevier. Get it on Amazon.
Cuccurullo, S. (2019). Physical medicine and rehabilitation board review. New York: Demosmedical. Get it on Amazon.
O’Young, B., Young, M.A. and Stiens, S.A. (2008). Physical Medicine and Rehabilitation Secrets. Mosby. Get it on Amazon.