Weight Loss Or Gain From Taking Naltrexone

Naltrexone is a medication commonly prescribed to help people recover from alcohol or opioid addiction by blocking the effects of these substances in the brain. As an opioid antagonist, naltrexone can sometimes cause side effects that lead to weight loss in certain patients, though weight changes vary significantly from person to person.

Doctors also prescribe low-dose naltrexone for purposes other than addiction treatment, such as helping with weight management or reducing inflammation in people with chronic pain conditions. Anyone considering naltrexone should have an honest discussion with their healthcare provider about potential benefits and risks, including weight-related effects, to determine if it’s the right treatment option for their specific medical situation.

Learn more about using Naltrexone for addiction treatment

Does Naltrexone Cause Weight Gain?

Weight gain is not a reported side effect of naltrexone, also known as Vivitrol. It’s more common for the opposite to occur, although certain personal factors can affect this. For example, many people with chronic substance use disorders are malnourished. This can affect everything from weight to mood, sexual health, and psychological well-being.

A person may gain weight as a result of factors unrelated to their use of naltrexone, such as restoring nutrition in early recovery, changes in fluid intake, digestive issues, and effects from other medications.

Does Naltrexone Cause Weight Loss?

Naltrexone can suppress a person’s appetite and have other side effects that could potentially lead to weight loss.

Effects of naltrexone that could cause weight loss include:

• reduced alcohol intake
• nausea or vomiting
• reduced appetite
• decreased food cravings
• diarrhea
• stomach pain

Changes in weight while taking naltrexone may be influenced by the dose taken, dietary habits, and other personal factors during treatment.

Is Naltrexone Prescribed For Weight Loss?

While naltrexone alone is not usually prescribed for weight loss, there is one FDA-approved weight management medication called Contrave that combines naltrexone with bupropion specifically for people with a high body mass index (BMI) who need assistance with weight management. This combination medication works differently than naltrexone medications used for addiction treatment, such as Vivitrol or ReVia, which are prescribed solely to help people recover from alcohol or opioid use disorders and are not intended or approved for weight loss purposes.

What Factors Can Affect Changes In Weight With Naltrexone?

Not everyone reacts to medications in the same way. When taking naltrexone for a substance use disorder, there are various factors that can influence changes in weight.

These factors might include:

• body mass index (BMI)
• changes in appetite
• changes in physical activity
• dose of naltrexone taken
• use of other substances
• genetic factors
• environmental factors

If you or a loved one is taking naltrexone and is concerned about changes in weight while on this medication, consider talking to your doctor for further guidance.

What Naltrexone Does To Appetite In Early Recovery

One of the more practical things to understand about naltrexone is how it can affect appetite and eating habits during early recovery, a time when nutrition already tends to be disrupted. Many people entering recovery for alcohol or opioid addiction are coming from a period of poor nutrition and irregular eating, and naltrexone’s appetite-suppressing effects can sometimes make it harder to restore healthy eating patterns. This is worth discussing with a doctor before starting the medication, particularly for anyone who is already underweight or dealing with nutritional deficiencies.

Some people in recovery find that reduced cravings for alcohol also translate into reduced cravings for sugar and processed foods that often accompany heavy drinking. This can actually support healthier eating over time. The key takeaway is that weight and appetite changes on naltrexone are highly individual and influenced by far more than the medication itself, including changes in activity level, sleep, stress, and overall lifestyle during recovery.

Find A Treatment Center That Offers Naltrexone Today

Naltrexone is a medication that can effectively reduce cravings for opioids and alcohol in addiction recovery. It has no known long-term side effects and is non-addictive. Naltrexone is offered by some addiction rehab centers and treatment providers as a medication-assisted treatment (MAT) option for people who have fully detoxed from drugs of abuse.

To find naltrexone treatment for yourself or a loved one with a substance use disorder, or for more helpful information about addiction recovery, reach out to the Substance Abuse and Mental Health Services Administration (SAMHSA).

Written by the Addiction Resource Editorial Staff