Buprenorphine and naloxone is a combination prescription medication used to treat opioid use disorder. Sold under brand names like Suboxone, it comes as a dissolving tablet or film placed under the tongue. The two ingredients work together: buprenorphine reduces cravings and withdrawal symptoms by partially activating the same brain receptors that opioids target, while naloxone is included to discourage misuse by injection.
How the Two Ingredients Work
Buprenorphine is what’s known as a partial opioid agonist. It binds to the same receptors in the brain that full opioids like heroin, fentanyl, or oxycodone activate, but it produces a much weaker effect. Think of it as a key that fits the lock but only turns partway. This partial activation is enough to ease withdrawal symptoms and reduce cravings, but it has a built-in ceiling: past a certain dose, taking more doesn’t increase the high. That ceiling effect makes it significantly safer than full opioids when it comes to the risk of respiratory depression, the cause of most overdose deaths.
Buprenorphine also binds to those receptors with unusually high affinity and dissociates very slowly. In practical terms, it latches on tightly and doesn’t let go easily. This means it can block other opioids from attaching to the receptor, reducing the reinforcing effects if someone uses other opioids while on treatment.
Naloxone is a pure opioid antagonist. It blocks opioid receptors entirely and produces no pain relief or euphoria. Its role in this combination is specifically to deter intravenous misuse. When the tablet or film dissolves under the tongue as directed, naloxone is barely absorbed into the bloodstream. But if someone crushes and injects the medication, naloxone’s bioavailability jumps dramatically, blocking the effects of buprenorphine and potentially triggering immediate withdrawal in someone dependent on opioids.
How It’s Taken
The medication is placed under the tongue (sublingual) and allowed to dissolve completely. It’s typically taken once a day. The recommended target dose is 16 mg of buprenorphine combined with 4 mg of naloxone, though maintenance doses range from 4/1 mg to 24/6 mg per day depending on individual needs.
Timing of the first dose matters enormously. Because buprenorphine has such strong receptor affinity, starting it too soon after using other opioids can cause something called precipitated withdrawal, a sudden and intense onset of withdrawal symptoms. To avoid this, you need to be in moderate withdrawal before taking the first dose. The required waiting period depends on what opioid was used: at least 4 hours after heroin, 36 to 48 hours after methadone, and 3 or more days after fentanyl. Clinicians use a standardized withdrawal scoring tool to confirm you’re ready before that first dose.
Common Side Effects
The most frequent side effects are typical of opioid-type medications: nausea, vomiting, headache, constipation, and sweating. These tend to be dose-related, meaning higher blood levels of buprenorphine increase their likelihood. Most people find side effects manageable and less disruptive than the cycle of active opioid use and withdrawal.
Allergic reactions, while uncommon, can include rashes, hives, and itching. Rarely, more serious reactions like severe swelling or breathing difficulty have been reported. There’s also a small risk of serotonin syndrome if the medication is combined with certain antidepressants or other drugs that raise serotonin levels. Symptoms of serotonin syndrome include agitation, rapid heartbeat, fever, and muscle twitching.
Respiratory depression, the slowed or stopped breathing that makes opioid overdoses fatal, is possible but far less likely than with full opioids due to buprenorphine’s ceiling effect. The risk increases substantially when combined with benzodiazepines, alcohol, or other sedatives.
Dental Health Risks
In 2022, the FDA added a warning about serious dental problems linked to buprenorphine products that dissolve in the mouth. A review of adverse event reports found 305 cases of dental damage, including tooth decay, cavities, oral infections, and tooth loss. These problems occurred even in people with no prior dental issues, with a median time to diagnosis of about two years after starting the medication.
Tooth extraction was the most commonly reported treatment, followed by root canals and dental surgery. If you take this medication, rinse your mouth with water after each dose (once it’s fully dissolved), wait at least an hour before brushing your teeth, and keep up with regular dental visits. The FDA recommends a baseline dental evaluation when starting treatment.
Controlled Substance Classification
Buprenorphine and all products containing it are classified as Schedule III controlled substances under federal law. This places it in a category of drugs considered to have moderate to low potential for dependence, alongside medications like testosterone and ketamine. Schedule III is notably less restrictive than Schedule II, where full opioid painkillers like oxycodone and fentanyl are classified.
How Prescribing Has Changed
For years, doctors needed a special federal waiver (called an X-waiver) to prescribe buprenorphine, and they were limited in how many patients they could treat. That requirement was eliminated in 2023. Now, any practitioner with a DEA registration and the authority to prescribe Schedule III controlled substances can prescribe buprenorphine for opioid use disorder, with no patient caps.
A 2025 federal rule also expanded access through telemedicine. Practitioners can now prescribe buprenorphine via video or phone visits for up to six months before an in-person evaluation is required. They must review the patient’s prescription drug monitoring program data before prescribing, a safeguard designed to flag potential interactions with other controlled substances. If that database is unavailable for any reason, they can issue a seven-day supply while attempting access again.
What Long-Term Treatment Looks Like
Buprenorphine and naloxone is designed for ongoing use, not just short-term detox. Research consistently shows that people who stay on medication-assisted treatment for longer periods have better outcomes: lower rates of relapse, fewer overdose deaths, and improved quality of life. There’s no standard timeline for stopping, and many people remain on it for years.
The medication does create physical dependence, meaning stopping abruptly will cause withdrawal symptoms. This is expected and is not the same as addiction. When the time comes to taper, it’s done gradually under medical supervision. The distinction is important: the medication replaces chaotic opioid use with a stable, controlled treatment that lets people return to normal functioning.
For pregnant individuals, buprenorphine is generally considered safer than continued illicit opioid use, though newborns may experience neonatal opioid withdrawal syndrome after delivery. This is a known, treatable condition that medical teams monitor for and manage in the hospital.