Movantik (naloxegol) is an opioid antagonist that's used to treat opioid-induced constipation, or constipation from opioid medications, in adults. It's a tablet that's taken by mouth once every morning on an empty stomach. The dosage is typically 25 mg, but it can be lowered to lessen side effects or risks from interactions with other medications. Common side effects include stomach pain, diarrhea, and nausea. Movantik (naloxegol) is available as a brand-name medication only; there's no lower-cost generic version yet.
Constipation is a common side effect of opioid pain medications. When you take an opioid, it can attach to opioid receptors in the intestines and affect how well your digestive system works. For example, it causes food and waste move through the gut slower.
Movantik (naloxegol) is an opioid antagonist. It blocks opioid receptors in the intestines so that opioid medications can't attach to these receptors. This helps to treat constipation caused by opioid medications so that you can go to the bathroom more easily.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
A good option to help with constipation from opioids
Taken by mouth once a day
Tablets can be crushed and mixed with water for people who have trouble swallowing them whole
Must take on an empty stomach
Might have opioid withdrawal symptoms
Might not work as well if you've been taking opioids for less than 1 month
Movantik (naloxegol) only works to treat constipation from opioid medications. It's not an antidote (reversal agent) and doesn't work to treat an opioid overdose. Always carry naloxone (Narcan), a medication that helps reverse the effects of opioids in situations like an accidental overdose.
Stop using other laxatives before you start taking Movantik (naloxegol). You can use other laxatives again as needed if you're still constipated after you've used Movantik (naloxegol) for 3 days.
Swallow the Movantik (naloxegol) tablet whole every morning on an empty stomach, at least 1 hour before or 2 hours after breakfast. Taking it with food can make your body absorb more Movantik (naloxegol), which can possibly affect how well your opioid medication works and raise your risk for withdrawal symptoms.
Movantik (naloxegol) can sometimes cause diarrhea. Make sure to stay hydrated if you have diarrhea while you're taking this medication. Seek medical help if you feel dizzy, lightheaded, or faint. Also get help right away if you have severe diarrhea; your dose might be too high.
Avoid eating grapefruit or drinking grapefruit juice. Grapefruit can raise the levels of Movantik (naloxegol) in the body and put you at risk for side effects.
Tell your healthcare team and pharmacist about all the other medications that you take. Movantik (naloxegol) interacts with many medications, and these interactions can be harmful. You might need to take a lower dose of Movantik (naloxegol) or stop taking one of your other medications to prevent side effects from drug interactions.
If you can't swallow Movantik (naloxegol) tablets whole: You can crush the tablet into a powder and mix with a half-cup of water. Stir and drink right after mixing. Stir in another half-cup of water and drink right after mixing to make sure you've taken all the medication. You can also give the medication through a nasogastric (NG) feeding tube; ask your prescriber or pharmacist about the proper technique.
Talk to your healthcare team about the risks and benefits of taking Movantik (naloxegol) while pregnant or breastfeeding. It's not clear how safe the medication is for people who are pregnant, planning to become pregnant, or breastfeeding. It's not recommended to take Movantik (naloxegol) while nursing to be safe.
Stop taking Movantik (naloxegol) if you stop treatment with your opioid medication. You'll need to use a different laxative if you continue to have constipation after you stop taking the opioid. Movantik (naloxegol) will no longer be helpful.
Movantik (naloxegol) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Taking methadone for pain
Although rare, some people who took Movantik (naloxegol) experienced withdrawal symptoms, such as sweating, chills, diarrhea, stomach pain, anxiety, and irritability. In studies, these symptoms were more likely to happen in people who took methadone for pain. In some rare cases, you might also get less pain relief from your opioid medication. Talk to your prescriber if you experience any withdrawal symptoms or if your pain medications aren't working as well anymore.
Risk factors: Taking 25 mg of Movantik (naloxegol)
Movantik (naloxegol) can cause stomach pain or diarrhea, which can be severe enough to require going to the hospital. These side effects can happen within a few days of starting Movantik (naloxegol). The side effects are more likely to happen if you're taking 25 mg of the medication per day. Let your prescriber know if you have severe stomach pain or diarrhea while you're taking Movantik (naloxegol). You'll probably need to have your dose lowered to 12.5 mg daily or be switched to a different medication.
Risk factors: Gastrointestinal cancer | Recent gastrointestinal surgery | Gastrointestinal inflammation such as Crohn's disease, diverticulitis, or colitis | Taking Avastin (bevacizumab)
In some rare cases, people who've taken Movantik (naloxegol) reported having stomach or gut problems, including inflammation or a tear in the wall of the gut. This can be dangerous and require hospitalization. Before you start Movantik (naloxegol), let your prescriber know if you have a history of bowel or gut-related problems. Notify your healthcare team right away if you have severe stomach pain, stomach pain that doesn't go away, worsening stomach pain, chills, or fever.
Allergic reactions to Movantik (naloxegol) are possible. People have reported allergic reactions, such as rash and hives. But some allergic reactions can be life-threatening and include facial swelling and anaphylaxis (closing of the throat). Get medical attention right away if you notice rash, hives, dizziness, a choking sensation, difficulty breathing, swelling around your eyes, or swelling of the lips or tongue after you take Movantik (naloxegol).
The typical dose is 25 mg by mouth once daily in the morning at least 1 hour before or 2 hours after breakfast.
Your prescriber might lower your dose if you're having side effects, if you have kidney problems, and if you're taking a medication that interacts with Movantik (naloxegol).
Medical conditions that cause blockage of the stomach passageway
Take certain medications that can interact with Movantik (naloxegol) (e.g., clarithromycin, itraconazole, ketoconazole)
Constipation due to opioid pain medications
Long-term constipation due to unclear cause (idiopathic)
Constipation due to opioids
Constipation due to irritiable bowel syndrome (IBS) in women 18 years or older
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Crockett, S. D., et al. (2018). American Gastroenterological Association Institute Guideline on the medical management of opioid-induced constipation. Gastroenterology.
Department of Justice and Drug Enforcement Administration. (2015). Schedules of controlled substances: removal of naloxegol from control. Federal Register.
MedlinePlus. (2022). Gastrointestinal perforation.
MedlinePlus. (2022). Nasogastric feeding tube.
RedHill Biopharma Ltd. (2020). Movantik- naloxegol oxalate tablet, film coated [package insert]. DailyMed.
Yoon, S. C., et al. (2017). Naloxegol in opioid-induced constipation: A new paradigm in the treatment of a common problem. Patient Preference and Adherence.
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