Three FDA-approved medications treat heroin addiction: methadone, buprenorphine, and naltrexone. Each works differently in the brain, and the best choice depends on where someone is in recovery, their daily routine, and their treatment goals. All three significantly reduce the risk of fatal overdose, with studies showing methadone lowers overdose death odds by 58% and buprenorphine by 52%.
How the Three Medications Work
Heroin activates opioid receptors in the brain, producing intense euphoria and physical dependence. The three medications for heroin addiction each interact with those same receptors, but in fundamentally different ways.
Methadone fully activates opioid receptors, much like heroin does, but it acts slowly and steadily rather than producing a rush. This eliminates withdrawal symptoms and cravings without the high. It has been used for over 50 years and remains one of the most studied addiction treatments available.
Buprenorphine partially activates opioid receptors. It provides enough stimulation to prevent withdrawal and reduce cravings, but it has a built-in ceiling effect: beyond a certain dose, taking more doesn’t increase the effect. This makes it harder to misuse and lowers the risk of overdose compared to full-strength opioids. Buprenorphine also blocks other opioids from attaching to receptors, so if someone uses heroin while on buprenorphine, the heroin’s effects are blunted.
Naltrexone takes the opposite approach. It blocks opioid receptors entirely, producing zero opioid effect. If someone takes heroin while on naltrexone, they won’t feel it. Unlike the other two medications, naltrexone carries no risk of physical dependence.
Methadone: Daily Dosing at a Clinic
Methadone is typically dispensed at specialized opioid treatment programs. For most of its history, patients had to visit a clinic daily to receive their dose under observation. Starting doses are kept low, usually 10 to 20 mg, and increased gradually by 5 to 10 mg every few days. The effective maintenance dose for most people falls between 60 and 120 mg per day. Reaching a stable dose can take several weeks.
Regulations updated in October 2024 give clinicians more flexibility with take-home doses. Providers no longer have to follow rigid time-in-treatment criteria before allowing patients to take methadone home. Instead, decisions are based on individual safety considerations and shared decision-making. This change makes methadone more practical for people with jobs, childcare responsibilities, or limited transportation. Telehealth screening for starting methadone is now also permitted under certain conditions.
Buprenorphine: Prescribed From a Doctor’s Office
Buprenorphine’s biggest practical advantage is that it can be prescribed in a regular doctor’s office or even through telehealth, rather than requiring daily clinic visits. The most widely known formulation is a combination of buprenorphine and naloxone, sold as a dissolving film placed under the tongue. The naloxone component is included specifically to discourage misuse: if someone tries to inject the film instead of taking it as directed, the naloxone triggers immediate, intense withdrawal. When taken under the tongue as prescribed, the naloxone has virtually no effect.
Starting buprenorphine requires careful timing. Patients need to be in moderate withdrawal before their first dose. If buprenorphine is taken too soon after heroin use, it can actually trigger what’s called precipitated withdrawal, a sudden and severe onset of withdrawal symptoms. Clinicians use a standardized 11-item scoring tool to confirm a patient is ready, and the first day’s dose is capped to allow the body to adjust. The whole induction process typically takes about two days, after which the dose is increased to a maintenance level, generally in the range of 4 to 24 mg per day.
For people who struggle with daily dosing, a monthly injectable form of buprenorphine is available. It’s given as a shot under the skin, starting with two monthly doses at a higher level, then stepping down to a lower maintenance dose. The injection sites rotate between the abdomen, thigh, buttock, or upper arm. This option removes the daily routine entirely and eliminates concerns about missed doses or diversion.
Naltrexone: The Non-Opioid Option
Naltrexone appeals to people who want a treatment that involves no opioid activity at all. It’s available as a daily pill or as a monthly injection given in a healthcare provider’s office. The injectable version delivers 380 mg once every four weeks, which solves the adherence problem that plagues the pill form. Missing oral doses leaves someone completely unprotected and vulnerable to relapse.
The major catch with naltrexone is the starting requirement. A person must be completely free of all opioids for at least 7 to 10 days before their first dose. If any opioids remain in the system, naltrexone will trigger severe withdrawal. For someone with heavy heroin dependence, that opioid-free window can be extremely difficult to achieve, which is why naltrexone tends to work best for people who have already completed detoxification, are leaving a controlled environment like jail or residential treatment, or are highly motivated to remain opioid-free.
Treatment During Pregnancy
Methadone and buprenorphine are both recommended as first-line treatments for pregnant women with heroin addiction. Stopping opioids abruptly during pregnancy is dangerous and can cause preterm labor, fetal distress, or miscarriage. Medication-assisted treatment produces better outcomes for both mother and baby and significantly reduces the risk of relapse.
Babies born to mothers on methadone or buprenorphine may experience neonatal abstinence syndrome, a temporary withdrawal condition that is expected and treatable. Medical guidelines are clear that this possibility alone should not discourage treatment. Naltrexone’s safety during pregnancy is not well established. If a woman is already stable on naltrexone before becoming pregnant, the decision to continue involves weighing limited safety data against the risk of relapse if the medication is stopped.
Choosing Between the Three
No single medication is universally best. The choice often comes down to logistics, severity of dependence, and personal preference. Methadone offers the most robust opioid replacement and works well for people with severe, long-standing addiction, but it requires the most structured treatment setting. Buprenorphine provides a middle ground with greater flexibility and a strong safety profile, making it the most commonly prescribed option in outpatient settings. Naltrexone suits people who have already detoxed and prefer a completely non-opioid approach, but the high barrier to entry limits who can realistically start it.
All three medications are most effective when combined with some form of counseling or behavioral support, though medication alone still substantially reduces the risk of overdose death and relapse. The critical point is that these medications are not simply substituting one drug for another. They stabilize brain chemistry, restore normal functioning, and give people the capacity to rebuild their lives while their brains heal from the changes heroin caused.