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Updated on August 8, 2025
Opioid use disorder (OUD) is a serious medical condition characterized by the compulsive and chronic use of opioid drugs, despite the negative impact that opioid consumption has on a person’s physical health, mental health, relationships, and quality of life.
OUD can involve the use of prescription opioid pain medications, illegal opioid drugs, or both. People with OUD will develop a tolerance to opioids, and over time will crave opioids in larger doses. They will also experience withdrawal symptoms if they reduce or stop opioid consumption.
It cannot be emphasized enough that OUD is a medical condition that requires treatment from medical professionals. It is not something a person can treat on their own.
It also cannot be emphasized enough that OUD is treatable. While treatment should be individualized and tailored to a person’s needs, a combination of medications for opioid use disorder (MOUD), counseling/therapy, and support is recommended.
The goal of treatment is to achieve and maintain recovery and allow a person to regain function in the areas of their life that have been impacted by OUD.
Medications for opioid use disorder (MOUD)
Medications fit into an OUD treatment plan in several ways. Some are prescribed during the initial detoxification phase, to manage symptoms of opioid withdrawal. It’s often recommended that people with OUD carry naloxone (commonly known as Narcan), which can be a life-saving emergency treatment if a person experiences opioid overdose.
There are also maintenance therapies. These medications can be safely taken for extended periods of time (in some cases, indefinitely) to help manage cravings and block the euphoric effects of opioid drugs, allowing a person to function.
Many people with OUD take maintenance therapy drugs daily in the form of tablets or powders that are mixed with liquid, sublingual films that dissolve under the tongue, or liquid solutions.
There are also long-acting maintenance therapy medications that are administered as injections by a healthcare provider. These are sometimes referred to as extended-release injectable or long-acting injectable (LAI) medications.
What medications are available as LAIs?
There are two main MOUD that are available in LAI formulations, buprenorphine and naltrexone. Both act on opioid receptors in the nervous system, proteins found on the surface of certain nerve cells. Each medication works in different ways:
- Naltrexone attaches to opioid receptors and blocks the receptors from working. This blocks the effects of opioids—a person who takes an opioid while taking naltrexone will not experience the effects of that opioid.
- Buprenorphine partially activates opioid receptors. This partial activation helps relieve withdrawal and cravings, but (when used as prescribed) it does not produce the same intoxication as an opioid drug.
A key difference between the two is that buprenorphine can also be used to treat opioid withdrawal. Before beginning treatment with naltrexone, a person must have completed opioid detoxification—LAI naltrexone cannot be used if a person has consumed opioids in the past 10 days. Similarly, this medication cannot be given if a person is currently drinking alcohol.
Both are considered effective treatments for helping a person maintain recovery, and each has their advantages and potential drawbacks—topics that are best discussed with the healthcare provider that will be prescribing a MOUD.
How does the “long-acting” part work?
The basic idea is that each medication is contained in a substance that is broken down slowly over time by the body. As the substance is broken down, medication is released slowly and steadily into the bloodstream.
Where are LAI injections administered?
Long-acting naltrexone injections are administered as an intramuscular injection into the buttocks. Long-acting buprenorphine injections are injected into the subcutaneous layer (a fatty layer just beneath the skin) in the abdomen, thigh, buttock, or upper arm. Either type must be administered by a healthcare provider.
How often do you need to take an LAI?
The dosing schedule will depend on the specific LAI being prescribed and the dosage. LAI buprenorphine is available in once-weekly or once-monthly dosages. LAI naltrexone is administered every four weeks.
Why might an LAI medication be recommended?
Different medications have different benefits and potential drawbacks and will work better for different people. For example, a LAI will require regular appointments with a healthcare provider, but also fewer treatments to a pharmacy or drug treatment clinic. It may also improve adherence —taking a medication each day can be challenging for any health condition.
All medications for OUD (and other conditions) carry a risk of adverse effects, which should be discussed with a healthcare provider before starting treatment. This conversation should include a discussion of a person’s medical history and overall health, including any coexisting conditions.
However, there is no best treatment for OUD, only the treatment that works best for an individual. There are many factors to be considered when choosing a MOUD, and a healthcare provider will be your best source of information.
