Nausea From Taking Naltrexone | Does Naltrexone Cause Nausea?

Naltrexone is a prescription medication used to treat alcohol use disorder and opioid addiction as part of medication-assisted treatment (MAT). It’s available in two forms: a daily pill sold under the brand names ReVia and Depade, or a monthly injection called Vivitrol. Naltrexone works by blocking opioid receptors in the brain, which reduces cravings for alcohol and opioids and helps prevent relapse during recovery.

One of the most common side effects people experience when taking naltrexone is nausea, which can range from mild queasiness to more severe stomach upset. This side effect typically occurs during the first few days or weeks of treatment as your body adjusts to the medication. For some people, the nausea goes away on its own after a short time, while others may experience it for longer periods.

Learn more about the side effects of taking Naltrexone

What Causes Nausea While Taking Naltrexone?

Naltrexone is an opioid antagonist that binds to and blocks opioid receptors in the brain, and alters the activity of the brain chemicals dopamine and serotonin. Nausea while taking naltrexone is believed to be tied to this interaction with the body’s opioid receptors, which are involved in the regulation of hormones, digestion, and pain perception.

Side effects while taking naltrexone can also be influenced by recent alcohol use, negative drug interactions, protracted opiate withdrawal, and taking naltrexone on an empty stomach.

How Naltrexone Forms Affect Nausea

The form of naltrexone you take can impact how likely you are to experience nausea and how severe it might be. Oral naltrexone tablets (ReVia, Depade) are taken daily and can cause nausea more frequently because the medication passes through your digestive system every day. Taking the pill on an empty stomach tends to make nausea worse, which is why doctors often recommend taking it with food or at bedtime to minimize this side effect.

Injectable naltrexone (Vivitrol) is given as a once-monthly shot in the buttocks muscle by a healthcare provider. While the injection form can still cause nausea, many people find it causes less stomach upset than the daily pill because the medication is released slowly into the bloodstream over time rather than all at once. However, some people experience nausea for a few days after receiving the injection as their body adjusts to the new dose.

Risk Factors For Nausea From Naltrexone Use

According to a study published in the Journal of Clinical Psychopharmacology, there are several risk factors that can predict nausea as a likely side effect while taking naltrexone.

Risk factors for experiencing nausea include:

• younger age
• being female
• recent alcohol use
• light drinking
• taking higher doses of naltrexone

Because the study only included participants receiving naltrexone for alcohol use disorder, the same risk factors may not apply for those taking it for opioid addiction.

Does Nausea From Naltrexone Go Away?

Side effects of naltrexone, such as nausea, may often subside within the first two to four weeks of initial use, as the body adjusts to the drug. However, this may not be true for everyone. The body’s reaction to drugs like naltrexone can vary from person to person based on a number of genetic, biological, and personal factors.

Tips For Managing Nausea While Taking Naltrexone

Nausea is one of the most common side effects of naltrexone. Unfortunately, this can sometimes disrupt treatment compliance, as in it can prompt a person to stop taking it. Side effects like nausea may go away with time. But if this isn’t the case, this effect may be manageable through a variety of means.

Tips and home remedies for managing nausea can include:

• taking naltrexone at bedtime (if taking pills)
• taking an antacid for nausea or vomiting
• avoid taking naltrexone on an empty stomach
• avoid alcohol while receiving naltrexone treatment

If you’re experiencing persistent nausea while taking naltrexone for drug or alcohol addiction, consider consulting your doctor for further guidance.

When To Contact Your Doctor About Nausea

While mild nausea is a common and usually manageable side effect of naltrexone, there are situations where you should contact your healthcare provider right away. Seek medical attention if you experience severe nausea that prevents you from eating or drinking, vomiting that lasts more than 24 hours, signs of dehydration like dark urine or dizziness, severe stomach pain, or vomiting blood. These symptoms could indicate a more serious reaction that needs immediate medical evaluation.

You should also contact your doctor if nausea persists beyond the first few weeks of treatment without improvement, if it’s significantly affecting your quality of life or ability to function, or if you’re considering stopping naltrexone because of the nausea. Your doctor may be able to adjust your dose, prescribe anti-nausea medication to take alongside naltrexone, recommend a different schedule for taking the medication, or discuss whether switching between the oral and injectable forms might help.

Learn More About Naltrexone For Addiction Today

Experiencing side effects while taking naltrexone is normal, especially during the first few weeks of treatment as your body adjusts to the medication. Common side effects like nausea, headaches, fatigue, or digestive issues often improve over time and can be managed with your doctor’s guidance. It’s important not to stop taking naltrexone suddenly without talking to your healthcare provider first, as they may be able to adjust your dose, switch you to a different form of the medication, or recommend strategies to minimize side effects while you continue treatment.

If you’re interested in naltrexone treatment or want to learn more about how this medication can support your recovery from alcohol or opioid addiction, help is available. An addiction specialist can answer your questions about naltrexone, explain how it works as part of medication-assisted treatment, and connect you with rehab centers and healthcare providers near you that offer naltrexone programs.

Written by the Addiction Resource Editorial Staff