From the Guidelines
Naloxegol (Movantik) is the primary medication used to counteract opioid-induced constipation, typically prescribed at a dose of 25 mg once daily. This medication works as a peripherally-acting mu-opioid receptor antagonist that blocks opioid binding in the gastrointestinal tract without affecting pain control, as it doesn't cross the blood-brain barrier significantly 1.
Key Points to Consider
- Naloxegol is recommended for patients with chronic non-cancer pain, and its use should be considered alongside basic constipation management strategies such as increased fluid intake, dietary fiber, and physical activity.
- For patients with renal impairment or those taking moderate CYP3A4 inhibitors, a reduced dose of 12.5 mg daily is recommended.
- Other options include methylnaltrexone (Relistor), which can be administered subcutaneously at 8-12 mg every other day, and lubiprostone (Amitiza) at 24 mcg twice daily with food.
- Patients should be aware that side effects may include abdominal pain, diarrhea, nausea, and flatulence, and they should discontinue use and contact their healthcare provider if severe abdominal pain or diarrhea occurs.
Mechanism of Action and Efficacy
The mechanism of action of naloxegol involves blocking the m-opioid receptors in the gut, thereby effectively restoring the function of the enteric nervous system 1. Studies have shown that naloxegol is effective in treating opioid-induced constipation, with a significant improvement in stool consistency and frequency compared to placebo 1.
Comparison with Other Agents
Naloxegol has been compared to other agents such as methylnaltrexone and lubiprostone, and has been found to be effective in treating opioid-induced constipation 1. However, the choice of agent may depend on individual patient factors, such as renal function and concomitant medications.
Clinical Guidelines and Recommendations
The American Gastroenterological Association has issued guidelines recommending the use of laxatives as first-line agents for opioid-induced constipation, with naloxegol being a recommended option for patients who do not respond to laxatives 1.
From the FDA Drug Label
MOVANTIK is an opioid antagonist indicated for the treatment of opioid-induced constipation (OIC) in adult patients with chronic non-cancer pain, including patients with chronic pain related to prior cancer or its treatment who do not require frequent (e.g., weekly) opioid dosage escalation. (1)
The medication that counteracts opioid-induced constipation is naloxegol (PO), also known by the brand name MOVANTIK 2.
- Key points:
- It is an opioid antagonist.
- Indicated for adult patients with chronic non-cancer pain.
- Treats opioid-induced constipation (OIC).
From the Research
Medications for Opioid-Induced Constipation
The medications that counteract constipation from narcotics include:
- Peripherally acting mu opioid receptor antagonists (PAMORAs) such as methylnaltrexone, naldemedine, and naloxegol 3, 4, 5
- Lubiprostone, linaclotide, or prucalopride 6
- Over-the-counter laxatives as first-line agents for opioid-induced constipation (OIC) and opioid-exacerbated constipation (OEC) 7
Efficacy and Safety of PAMORAs
PAMORAs have been shown to be safe and effective in alleviating constipation without diminishing the analgesic effect of opioid therapy 3, 4, 5. They work by antagonizing the effects of opioids in the gastrointestinal system, allowing for normal bowel function to resume.
Treatment Options
Treatment options for OIC include: