Naltrexone is a medication used to treat opioid (e.g. heroin, morphine) and alcohol dependenceaddiction. It works by blocking the opioid receptor (a molecule that opioids bind to) to prevent opioid “highs” and any pleasure experienced while drinking alcohol. It also reduces cravings for these substances. Naltrexone is available in daily oral (pill) and monthly injectable forms by prescription only.

Naltrexone is most frequently used to treat addiction and to opioids and alcohol. It is also sometimes used to rapidly reverse the effects of opioid intoxication or overdose. However, naltrexone can cause symptoms of withdrawal in patients who are using opioid drugs. Therefore, treatment is started after the body is free of opioids, as demonstrated by the patient providing a clean urine sample. 

Limited studies on this medication have also shown some promise in the treatment of conditions associated with compulsive behaviors (e.g., compulsive sex, gambling addiction, smoking). Researchers are also studying the potential benefits of Naltrexone in the treatment of other conditions, such as Crohn’s disease, a chronic disorder of the digestive tract.

Common side effects of naltrexone include mild to moderate abdominal pain, anxiety, headache, nausea, vomiting and fatigue. The medication does not cause overdose.

Patients should not take naltrexone if they have any allergies to naltrexone or its derivatives. Naltrexone should not be taken by patients with hepatitis or any other liver disease because of an increased risk for liver damage.

Naltrexone should not be taken with any drugs that contain narcotics. This medication is not recommended for women who are pregnant or may become pregnant, women who are breastfeeding, or children. There have been very few studies of naltrexone in elderly patients. However, the medication seems to be similarly effective and as well-tolerated in older adults as it is in younger patients.

Naltrexone is a prescription medication that works to block the pleasurable brain effects of opioids and alcohol. It is used to treat addiction to opioid drugs and alcohol. Naltrexone is only one aspect of the complex treatment plans for these addictions. These treatments plans are individualized to the patient and frequently include counseling and support group meetings.

Naltrexone is an opioid receptor antagonist, and works by blocking the receptors that opioids bind to.  This results in diminished euphoria, reduced cravings and greater ease in managing the addiction.

Naltrexone is not a narcotic. It will not cause euphoria, addiction or dependence. However, it will not prevent alcohol intoxication. If taken by patients who are currently  taking opioid drugs, naltrexone may cause symptoms of opioid withdrawal.

Until recently, naltrexone was only available in pill form and had to be taken on a daily basis. However, in April 2006, the Food and Drug Administration (FDA) approved an injectable version of the drug that is administered once a month for the treatment of alcoholism. The new form of the drug helps ensure that patients are adhering to their treatment plan by ridding them of the temptation to skip their daily dose of naltrexone in order to experience the pleasurable effects of alcohol.

Naltrexone is only available by a physician’s prescription. The exact duration of naltrexone treatment depends on the individual patient and the specifics of the patient’s addiction. However, the medication is frequently taken for 12 weeks or longer. It is available under the brand names ReVia and Depade. Liver function tests are required before naltrexone is prescribed and every month for six months thereafter.

Naltrexone was originally developed to treat opioid addiction. It is also sometimes used to rapidly reverse the effects of opioid intoxication or overdose. However, naltrexone may cause symptoms of withdrawal in patients who are currently taking opioid drugs.

Once the patient has undergone detoxification and is no longer experiencing withdrawal symptoms, naltrexone is used to curb the cravings and diminish the effects if the drug is used.

Naltrexone is also frequently used to treat alcohol dependency. Unlike certain other medications used in the treatment of alcoholism, naltrexone does not cause adverse effects if alcohol is consumed during treatment.

Naltrexone has shown some promise in the treatment of several other conditions. Most of these are associated with compulsive behavior. These include compulsive sex, gambling addiction, self-injury and eating disorders. It appears that naltrexone may block the compulsions in much the same way that it blocks opioid or alcohol cravings. When acting on compulsions results in a release of pleasure, naltrexone may also be able to block that feeling. However, studies of the effects of naltrexone on these conditions have been limited and more research is required.

Preliminary research also indicates that the drug may be beneficial in reducing symptoms of Crohn’s disease, a chronic disorder of the digestive tract.

Most patients taking naltrexone do not experience any significant side effects. When side effects do occur, they often diminish over time as the body adapts to the medication. If any side effects persist or worsen, it is strongly recommended that patients contact a physician.

Common side effects of naltrexone include:

• Mild to moderate abdominal pain or cramping
• Anxiety, restlessness or trouble sleeping (insomnia)
• Headache, joint or muscle pain
• Nausea or vomiting
• Fatigue
• Diarrhea

Less common side effects include:

• Chills or dizziness
• Constipation
• Fast or pounding heartbeat
• Increased thirst
• Loss of appetite
• Sexual problems (in men)
• Irritability
• Cough, sneezing, runny or stuffy nose, hoarseness, sore throat or other sinus problems

More serious side effects are rare, but may occur. Patients are urged to seek medical attention if they experience any of the following:

• Fever
• Skin rash
• Severe abdominal pain
• Blurred vision or eye pain
• Chest pain
• Difficult or frequent urination
• Hallucinations
• Itching
• Ringing in the ears
• Shortness of breath
• Swelling of the face, feet or legs
• Unexplained weight gain
• Confusion, depression or other mood or mental changes

Patients should consult their physician before taking any additional prescriptions, over-the-counter medications, nutritional supplements or herbal medications. Naltrexone must be used with caution with certain medications used to treat schizophrenia (e.g., thioridazine). This combination can result in sleepiness.

Narcotics are of particular concern to individuals taking naltrexone. Naltrexone should not be taken with any drugs that contain opioids. All narcotics must be stopped seven to 10 days before starting naltrexone treatment and abstinence must be verified with a clean urine test. Naltrexone may block the effects of these medications.

Patients who are dependent on narcotics experience withdrawal symptoms when taking naltrexone. High amounts of narcotics may overcome the effects of this medication. This may lead to oversensitivity to narcotic effects and overdose symptoms. In some cases, coma or death may occur.

Naltrexone does not cause overdose. Patients are advised to speak with a physician about the serious side effects of this medication.

Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following naltrexone-related questions:

1. Why do I need to take naltrexone?
   
   
2. I understand that naltrexone is only part of my treatment. What else will treatment include?
   
   
3. For how long will I need to take naltrexone?
   
   
4. What dosage of naltrexone should I take and how often should I take it?
   
   
5. How will naltrexone affect my other conditions? How may my other conditions affect naltrexone?
   
   
6. Could naltrexone interact with any of my other medications?
   
   
7. Will any of my other medications need to be changed? For example, if I can no longer take opioid analgesics, what can I take to treat my pain?
   
   
8. Given my medical history, are there any side effects I should be watching for? If so, what are they?
   
   
9. If I forget to take a dose of naltrexone, what should I do?
   
   
10. What if naltrexone does not seem to work for me?
    
    
11. What happens if I drink alcohol while I am receiving naltrexone treatment?