II. Indications
- Severe refractory Constipation due to Opioids
III. Mechanism
IV. Medications
-
Naloxegol (Movantik) once daily orally in morning ($10/day)
- FDA approved for non-cancer, Opioid-Induced Constipation
- Requires Renal Dosing adjustment
- Chey (2014) N Engl J Med 370:2387-96 [PubMed]
-
Methylnaltrexone (Relistor) injection ($70/day)
- Methylnaltrexone 5 mg or 0.15 mg/kg SQ
- Weight-based SQ Injection once or twice daily
- Diarrhea occurs in 8% and Abdominal Pain in 13%
- Requires Renal Dosing adjustment
- Contraindicated in Intestinal Obstruction
- Exercise caution in intestinal malignancy
-
Naldemedine (Symproic)
- Dose: Orally once daily
- No renal dose adjustment needed
-
Alvimopan (Entereg)
- Approved only for short-term management of post-operative ileus
- Restricted prescribing due to risk of Myocardial Infarction
V. Advantages
- Does not cross blood-brain barrier
VI. Disadvantages
- All agents in this class are expensive as of 2017 (costs range between $10 to $70 per day)
VII. Efficacy
- In general, results in one more Bowel Movement per week and may spare Laxative use
- Refractory Opioid Induced Constipation in Cancer and Palliative Care
- Both oral Naldemedine (Symproic) and SQ Methylnaltrexone (Relistor) are effective with benefits outweighing harms
- Brown (2023) Am Fam Physician 107(2):131-2 [PubMed]
- Terminally ill patients
- Bowel Movement occurs within 4 hours of dose in 48% of patients (15% wiith Placebo)
- Median time to Bowel Movement is 45 minutes (>6 hours for Placebo)
VIII. References
- (2017) Presc Lett 24(12): 70
- Portenoy (2008) J Pain Symptom Manage 35(5): 458-68 [PubMed]
- Thomas (2008) N Engl J Med 358(22): 2332-43 [PubMed]