Nalmefene, marketed under the brand name Opvee®, is a medication used primarily in the treatment of opioid use disorder (OUD). Nalmefene is an opioid antagonist that works by blocking the effects of opioids and reducing the risk of overdose. Although this medication shares similarities with the well-known naloxone, nalmefene has some unique distinctions and advantages, making it a valuable tool in the fight against opioid addiction.
Opvee® is the brand name for nalmefene, and it is available in various forms, including tablets and injections. This versatility allows healthcare providers to choose the most appropriate administration method based on the patient’s needs and circumstances. Approved by the Food and Drug Administration (FDA) in May 2023 for use in opioid addiction treatment, Opvee® is becoming an increasingly popular choice among healthcare providers as part of comprehensive medications for addiction treatment (MAT) programs.
As mentioned previously, nalmefene is an opioid antagonist that serves a crucial role in the management of opioid addiction. Unlike some treatments that only address the immediate dangers of overdose, nalmefene is designed for both emergency intervention and long-term support. It works by binding to opioid receptors in the brain, blocking the effects of opioids and helping to reduce cravings. This dual-action capability makes Nalmefene a valuable tool not only in reversing the life-threatening effects of an overdose but also in supporting sustained recovery efforts.
Nalmefene operates by binding to opioid receptors in the brain, effectively blocking the effects of opioid drugs like heroin, fentanyl, and prescription painkillers. By occupying these receptors, nalmefene blocks the effects of opioids, including the intense feelings of pleasure (or “high”) that often lead to addiction. This makes nalmefene a key player in both preventing opioid overdoses and supporting long-term recovery.
When someone uses an opioid, the drug connects to specific receptors in the brain, leading to a rush of dopamine—a chemical that creates feelings of pleasure and euphoria. This pleasurable feeling is a primary reason why opioid addiction can be so powerful. Nalmefene breaks this cycle by taking up space on those same receptors, stopping opioids from having any effect.
What sets nalmefene apart is that it stays active in the body longer than other treatments, like naloxone. This extended action means nalmefene continues to protect against relapse and overdose for a more extended period, helping individuals stay on track in their recovery journey and providing protection during the vulnerable time following an overdose.
Nalmefene (Opvee®) and naloxone (Narcan®) are both medications used to counteract the effects of opioids, but they serve different purposes and have some key differences. Here’s how they compare:
While both nalmefene and naloxone are crucial in managing opioid dependence and addiction, nalmefene is better suited for long-term treatment and relapse prevention. In contrast, naloxone is focused solely on immediate overdose reversal.
Nalmefene (Opvee®) and medications like Suboxone® (a combination of buprenorphine and naloxone) are both used to support individuals in achieving long-term sobriety from opioid addiction. However, they operate differently and serve distinct roles in the recovery process. Here are a few of the ways these medications differ from one another:
Nalmefene: Nalmefene is an opioid antagonist, meaning it completely blocks opioid receptors in the brain. By preventing opioids from activating these receptors, nalmefene eliminates the euphoric effects that drive addiction. This makes it particularly effective in preventing relapse by ensuring that even if someone takes opioids, they will not experience the desired effects.
Suboxone®: Suboxone®, on the other hand, contains buprenorphine, a partial opioid agonist, along with naloxone, an opioid antagonist. Buprenorphine activates opioid receptors but to a much lesser degree than full agonists like heroin or prescription opioids. This partial activation helps to reduce withdrawal symptoms and cravings without producing a significant high, allowing individuals to stabilize their condition. The naloxone component is included to deter misuse by injection.
Nalmefene: Nalmefene is typically used in individuals who have already detoxed from opioids and are committed to maintaining long-term sobriety. Its primary role is to prevent relapse by blocking the effects of any opioids that might be used.
Nalmefene does not relieve withdrawal symptoms or cravings on its own; instead, it ensures that if an individual does relapse, the opioids will not produce their usual effects, thereby reducing the incentive to continue using.
Suboxone®: Suboxone® is used both during the detoxification phase and in long-term maintenance therapy. It helps manage withdrawal symptoms and cravings, making it easier for individuals to transition away from opioid use.
By partially activating opioid receptors, Suboxone reduces the severity of withdrawal symptoms and cravings, which can be crucial in the early stages of recovery. Suboxone® can be used for extended periods, sometimes for months or even years, to help individuals stabilize and reduce the risk of relapse.
Nalmefene: As an opioid antagonist, nalmefene does not activate opioid receptors and, therefore, has no potential for abuse or dependence. This makes it a safe option for long-term use in individuals who are committed to maintaining sobriety.
Suboxone®: Buprenorphine, the active component in Suboxone®, is a partial opioid agonist, which means there is a potential for physical dependence, although it is much lower than with full agonists like heroin or prescription opioids. However, when used as prescribed, Suboxone® is an effective tool in helping individuals manage their addiction and gradually taper off opioids.
Related: Learn More About Suboxone Therapy
Nalmefene: Nalmefene is best suited for individuals who are already stable in their recovery and have successfully detoxed from opioids. Its role is to prevent relapse rather than to assist with the initial withdrawal process. It is particularly beneficial for those who are at high risk of relapse and need ongoing protection against the effects of opioids.
Suboxone®: Suboxone® is often used at the beginning of the recovery process to help individuals transition from opioid dependence to sobriety. It is also effective in long-term maintenance therapy for individuals who need ongoing support to manage cravings and withdrawal symptoms. Suboxone®’s ability to relieve withdrawal symptoms makes it a critical tool in the early stages of recovery.
While nalmefene is an effective tool in treating opioid addiction, it’s essential to be aware of potential risks with any medication you consider taking, especially for life-threatening conditions like substance use disorder (SUD). Here’s a deeper look at the risks associated with nalmefene for opioid addiction:
Like all medications, nalmefene can cause side effects, and individuals need to be aware of these as they begin treatment. Common side effects associated with nalmefene use include:
These side effects are generally mild and often diminish over time as the body becomes accustomed to the medication. Nausea and dizziness are among the more commonly reported effects, typically occurring in the initial stages of treatment. Headaches and fatigue can also manifest, mainly as the body adjusts to the changes in brain chemistry brought about by blocking opioid receptors.
One of the more severe risks associated with nalmefene is the potential for precipitated withdrawal. This occurs when Nalmefene rapidly displaces opioids from their receptors in the brain, leading to sudden and intense withdrawal symptoms. These symptoms can include severe anxiety, agitation, sweating, nausea, vomiting, and muscle aches.
The risk of precipitated withdrawal is exceptionally high if nalmefene is taken shortly after opioid use, as the body may still have significant levels of opioids in the system. This can be a distressing experience, so nalmefene should be used under strict medical supervision, especially during the early stages of treatment.
Nalmefene may interact with other medications, especially those that influence the brain and nervous system, such as sedatives, antidepressants, or other drugs used in mental health treatment. These interactions can alter nalmefene’s effectiveness or increase the risk of adverse side effects.
Always provide your healthcare provider with a complete list of all medications, supplements, and over-the-counter drugs you are taking. This information will help your doctor manage potential interactions and adjust your treatment plan accordingly, ensuring your safety and the effectiveness of your recovery.
The psychological impact of Nalmefene can be challenging, particularly for those in the early stages of recovery. By blocking the euphoric effects of opioids, Nalmefene removes the rewarding sensation that often drives addiction. For some individuals, this lack of a “high,” along with potential side effects, can lead to feelings of frustration, increased anxiety, or even a sense of loss, primarily if they have relied on opioids as a coping mechanism. This can lead to thoughts about using or even withdrawing from treatment. These psychological challenges highlight the importance of having professional oversight and support in place to help manage these emotions and reinforce the commitment to recovery.
Although uncommon, allergic reactions to Nalmefene can occur and may be severe. Symptoms could include a rash, itching, swelling (especially of the face, tongue, or throat), severe dizziness, or difficulty breathing.
These reactions require immediate medical attention, as they can escalate quickly. If you experience any signs of an allergic reaction after taking nalmefene, it is crucial to seek medical help immediately. Your healthcare provider will assess the situation and may recommend discontinuing the medication or finding an alternative treatment option.
For individuals considering nalmefene as part of their addiction treatment plan, it is essential to understand what to expect. Opvee® is typically prescribed as part of a comprehensive MAT program and should be used alongside other forms of therapy. Here are the highlights regarding what you should know about this medication:
At Porch Light Health, we understand the challenges of overcoming opioid addiction. With telehealth treatment options and over 60 points of care, including walk-in and mobile clinics, across Colorado and New Mexico, we are committed to ensuring you can access the treatment you need, no matter where you are. Our comprehensive medications for addiction treatment (MAT) programs are designed to support you at every stage of your recovery journey, offering the tools and resources needed to achieve lasting sobriety.
If you or a loved one is struggling with opioid addiction, don’t wait. Contact Porch Light Health today to learn about our addiction treatment programs, including MAT and virtual intensive outpatient treatment. Together, we can help you reclaim your life from addiction.
1. U.S. Food and Drug Administration. (n.d.). Information about naloxone and nalmefene. U.S. Department of Health and Human Services. Retrieved August 27, 2024, from https://www.fda.gov/drugs/postmarket-drug-safety-information-patients-and-providers/information-about-naloxone-and-nalmefene
2. Johansen, K. G. V., Tarp, S., Astrup, A., Lund, H., Pagsberg, A. K., & Christensen, R. (2017). Harms associated with taking nalmefene for substance use and impulse control disorders: A systematic review and meta-analysis of randomised controlled trials. PloS one, 12(8), e0183821. https://doi.org/10.1371/journal.pone.0183821
3. Green, M., Veltri, C. A., & Grundmann, O. (2024). Nalmefene Hydrochloride: Potential Implications for Treating Alcohol and Opioid Use Disorder. Substance abuse and rehabilitation, 15, 43–57. https://doi.org/10.2147/SAR.S431270
4. Kunzler, N. M., Wightman, R. S., & Nelson, L. S. (2020). Opioid withdrawal precipitated by long-acting antagonists. The Journal of Emergency Medicine, 58(2), 245-253. https://doi.org/10.1016/j.jemermed.2019.12.015
