Can Naltrexone Cause Hallucinations?

Hallucinations are a rare but serious side effect of naltrexone, a medication that is also sold under the brand names Vivitrol, ReVia, and Depade.

Naltrexone is primarily prescribed as a medication-assisted treatment option for opioid use disorder and alcohol dependence. It can block the euphoric effects of these substances and prevent drug or alcohol cravings.

Find out more about the side effects of Naltrexone

What Types Of Hallucinations Can Be Caused By Naltrexone?

The term ‘hallucination’ refers to a sensory experience that can alter someone’s perception of themselves or their surroundings.

Common types of hallucinations include:

• visual hallucinations: seeing things that aren’t there (e.g. patterns, lights, objects)
• auditory hallucinations: hearing things that aren’t there (e.g. voices, music, footsteps)
• tactile hallucinations: feeling a sensation (e.g. bugs crawling on skin)

The primary types of hallucinations associated with naltrexone use are visual and auditory. However, this side effect is rare and does not occur in most people taking it.

What Can Cause Hallucinations While Taking Naltrexone?

Hallucinations can occur as a result of a variety of causes, including the use of certain drugs, severe malnutrition, drug or alcohol withdrawal, and some mental health disorders.

What causes hallucinations in some who take naltrexone is unclear, although it may be linked to its effects of naltrexone on certain neurotransmitters, or chemicals, in the brain.

Potential causes and risk factors for hallucinations include:

• taking naltrexone with opioids still in your system
• use of illicit drugs or alcohol while taking naltrexone
• co-occurring mental illness (e.g. schizophrenia)
• history of psychosis

Are Hallucinations From Naltrexone Common?

Hallucinating while taking naltrexone as directed is not common. This is an adverse side effect that can occur, but is fairly rare. Hallucinations and other serious side effects may occur if naltrexone treatment is initiated prematurely, that is, before a person is fully detoxed from substances of abuse.

Taking naltrexone with opioids still in your system, or taking opioids while on naltrexone, could result in severe opioid withdrawal symptoms, including agitation and hallucinations.

What To Do If You Hallucinate While Taking Naltrexone

Seeing or hearing things that aren’t there after taking naltrexone can be a sign of an adverse drug reaction.

If this does occur, contact your prescribing doctor right away for further guidance.

Other Serious Side Effects Of Naltrexone

While hallucinations are rare, naltrexone can cause other serious side effects requiring immediate medical attention. Severe allergic reactions include rash, hives, swelling of face or throat, difficulty breathing, and severe itching. Liver damage is another serious concern, particularly at higher doses, with warning signs like dark urine, yellowing of skin or eyes (jaundice), extreme fatigue, or severe stomach pain.

Other serious side effects include severe depression, suicidal thoughts, confusion, severe nausea and vomiting, and signs of pneumonia like coughing, fever, and trouble breathing. Injection site reactions from Vivitrol can become serious with severe pain, hard lumps, or signs of infection. If you experience any of these symptoms, contact your healthcare provider or seek emergency medical care.

Staying Safe While Taking Naltrexone

To minimize the risk of hallucinations and other side effects, follow your doctor’s instructions exactly and never adjust your dose without guidance. Before starting naltrexone, ensure you’re completely opioid-free for at least seven to ten days to prevent precipitated withdrawal.

Avoid alcohol and illicit drugs while taking naltrexone, as combining substances increases adverse reactions. Inform all healthcare providers you’re taking naltrexone, especially in emergencies, since it blocks opioid pain medications. Attend all follow-up appointments for monitoring. Keep a list of any side effects to discuss with your doctor.

If you have a history of mental health issues like psychosis, make sure your prescriber knows before starting treatment. Wearing a medical alert bracelet indicating you take naltrexone can be helpful in emergencies.

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Written by the Addiction Resource Editorial Staff