Key takeaways
Naltrexone is a generic medication used to treat alcohol dependence and opioid use disorder.
Naltrexone may interact with certain medications, including opioids, certain cough medicines, and some antidiarrheals.
Taking naltrexone with a drug that contains an opioid, can cause opioid withdrawal symptoms.
Ways to minimize naltrexone interactions include sharing a list of all over-the-counter and prescription drugs, vitamins, and supplements you take with your provider and knowing the warning signs of a naltrexone interaction.
Naltrexone, also known by its brand-name counterpart Vivitrol, is by the U.S. Food and Drug Administration (FDA) to treat opioid use disorder and alcohol use disorder. It comes as an oral tablet and intramuscular (IM) injection. The tablet is typically taken once daily, and the injection is given once per month. Naltrexone belongs to a group of drugs called opioid antagonists, which work by blocking the effects of alcohol and opioids.
While naltrexone is an effective treatment option for alcohol and opioid dependence, it has the potential to interact with other medications. These include opioid medications, some cough and cold drugs, and medications for diarrhea.
Read on to learn more about potential naltrexone interactions.
Naltrexone drug interactions
Because of the way naltrexone works, it may interact with drugs that contain opioids. Here are some examples of drugs that can interact with naltrexone.
Opioids
Opioid drugs are used to manage severe pain. They work by binding to specific receptors in the body, which changes the way the body perceives pain. This helps you feel less pain. Naltrexone is an opioid antagonist, meaning it blocks the opioid receptors to block the effects of opioids.
Examples of opioids include:
- MS Contin (morphine)
- Ultram (tramadol)
- Fentanyl
- Roxicodone, Oxycontin (oxycodone)
- Percocet (oxycodone/acetaminophen)
If you’re taking opioids and start naltrexone, opioids won’t be as effective. And if you’re dependent on opioids, this can result in opioid withdrawal–a potentially life-threatening condition. Symptoms of opioid withdrawal include tearing, runny nose, goosebumps, muscle pain, light sensitivity, trouble sleeping, yawning, fast heart rate, high blood pressure, and high body temperature.
Due to this risk, it’s recommended to stop all opioid use a minimum of 7 to 10 days before starting naltrexone. And if you’re treating opioid use disorder with naltrexone and relapse, stop taking naltrexone and contact your healthcare provider right away.
Certain cough medications
Certain prescription cough medications contain opioids. Similar to its interaction with opioid drugs, taking naltrexone with cough medications containing opioids can cause opioid withdrawal.
Examples include:
- Promethazine/codeine
- Tuxarin ER (chlorpheniramine/codeine)
- FlowTuss (hydrocodone/guaifenesin)
- Hydrocodone/homatropine
For this reason, healthcare professionals typically won’t prescribe opioid-containing cough medications if you’re taking naltrexone. They will likely recommend an alternative treatment for your cough.
Certain diarrhea medications
Some prescription diarrhea medications contain opioids as well. Examples include Lomotil (diphenoxylate/atropine). Therefore, opioid withdrawal can occur if you take naltrexone with an opioid-containing antidiarrheal.
It’s important to note that Imodium (loperamide) works similarly to an opioid. So there is a risk of opioid withdrawal if it’s combined with naltrexone treatment.
Other opioid antagonists
Naltrexone belongs to a group of drugs called opioid antagonists. Opioid antagonists are used for a variety of medical conditions, including alcohol use disorder, opioid use disorder, opioid-induced constipation, and opioid overdose.
Examples of other opioid antagonists include:
Because all opioid antagonists work similarly, they typically have similar side effects. Therefore, combining multiple opioid antagonists may increase the risk of these side effects. Examples include nausea, vomiting, dizziness, loss of appetite, trouble sleeping, and headache.
Disulfiram
Similar to naltrexone, disulfiram is used to treat alcohol use disorder. Individually, they can both cause liver problems. Therefore, combining these medicines can increase the risk of liver problems.
Thioridazine
Thioridazine is an antipsychotic medication used to treat schizophrenia. Thioridazine and naltrexone can both cause sleepiness when taken alone. Taking these drugs together can worsen this side effect.
Vyleesi (bremelanotide)
Vyleesi (bremelanotide) is a drug used to treat low sexual desire in certain women. However, it has the potential to interact with naltrexone. When these drugs are taken together, Vyleesi (bremelanotide) can lower the body’s absorption of naltrexone. This can make naltrexone less effective. For this reason, healthcare providers typically won’t prescribe Vyleesi (bremelanotide) if you’re taking naltrexone.
Naltrexone food interactions
Sometimes foods can interact with medications. Fortunately, naltrexone isn’t known to interact with any foods.
Other naltrexone interactions
Naltrexone may also interact with alcohol, certain medical conditions, cannabis, and certain lab tests.
Naltrexone and alcohol
Although there aren’t any significant or dangerous effects from mixing alcohol and naltrexone, it’s recommended to avoid alcohol while taking naltrexone. Naltrexone can lessen cravings to drink alcohol and block the pleasure you feel while drinking. However, you can still become impaired with loss of coordination, difficulty with concentration, and slowed reactions if you mix the two.
What’s more, alcohol and naltrexone can both cause liver damage. Combining the two can increase the risk of liver damage.
Naltrexone and CBD
Cannabis and cannabis products, including cannabidiol (CBD), can also interact with naltrexone. Mixing naltrexone with cannabis can increase the effects of cannabis. Due to this risk, it’s important that your healthcare team is aware that you use cannabis before you start treatment with naltrexone.
Naltrexone and disease
Certain health conditions or health factors can increase the risk of side effects of naltrexone. These include people who have:
- Kidney disease
- Liver disease
- Opioid withdrawal symptoms
- Taken opioids in the last 7 to 10 days
- Had an allergic reaction to naltrexone or any of its ingredients
As with all medications, if you’re pregnant or breastfeeding, talk with your healthcare provider before taking naltrexone. It’s not known if naltrexone can harm your unborn baby or if it will pass into your breast milk and harm your breastfed baby.
Naltrexone and lab tests
Naltrexone can interact with certain urine lab tests that check for the presence of opioid drugs. Before taking any urine drug tests, be sure your provider is aware that you are taking naltrexone.
How to minimize naltrexone interactions
Minimizing naltrexone drug interactions is important to ensure safe and effective therapy. Before you start any new medications, consult with a healthcare professional. Provide them with an updated list of all prescription and over-the-counter medications, vitamins, and supplements you take. And discuss your medical history with them. This way, they can identify any potential naltrexone interactions before they occur.
It’s important to know the warning signs of a naltrexone interaction as well. If you’re taking naltrexone and experience any new or worsening side effects, such as nausea, vomiting, dizziness, or loss of appetite, consult with a medical professional. Additionally, report any new or worsening symptoms of your medical conditions, as this may be another sign of a drug interaction.
When to talk to a healthcare provider about naltrexone interactions
While many naltrexone interactions are discussed in this article, there may be other interactions we haven’t discussed. Communicating openly with your healthcare team about all medical conditions you have and medications you take is the best way to identify potential naltrexone interactions. While some interactions require close monitoring or a dosage adjustment, other medications aren’t safe to combine and shouldn’t be taken together. Keeping open communication with your healthcare provider ensures proper management and monitoring of your health.
Sources
- Consumer health group warns of loperamide abuse, misuse, American Academy of Family Physicians (2019)
- Interaction between naltrexone and oral THC in heavy marijuana smokers, Psychopharmacology (2003)
- Naltrexone, StatPearls, National Institute of Health (NIH) (2023)
- Naltrexone & alcohol: can I drink while on naltrexone? American Addiction Centers (2024)
- Naltrexone hydrochloride–naltrexone hydrochloride tablet, film coated prescribing information, Food and Drug Administration (2024)
- Opioid withdrawal, StatPearls, National Institute of Health (NIH) (2023)
- Vyleesi–bremelanotide injection prescribing information, Food and Drug Administration (2021)