What Happens if I Drink Alcohol While Taking Naltrexone?

Naltrexone does not make you sick if you drink on it, and it will not prevent you from getting drunk. What it does is strip away much of the pleasure alcohol normally delivers. The drug blocks opioid receptors in the brain, which dampens the rush of feel-good chemicals that alcohol typically triggers. You can still drink, you can still become intoxicated, but the experience feels flatter and less rewarding. Over time, that blunted reward signal can change your relationship with alcohol in ways that simply white-knuckling through sobriety often does not.

How Naltrexone Changes the Way Alcohol Feels

When you drink without naltrexone, alcohol triggers the release of endorphins, your body’s own opioid-like chemicals. Those endorphins bind to opioid receptors and set off a cascade that floods the brain’s reward circuitry with dopamine. That dopamine surge is what produces the warm buzz, the social loosening, the “this feels great” sensation that keeps people coming back for another round. Naltrexone parks itself on those same opioid receptors and blocks endorphins from binding, so the dopamine surge is muted before it starts.¹

In practical terms, people on naltrexone describe drinking as oddly unsatisfying. A controlled study found that participants on 50 mg of naltrexone reported less desire to drink both before and after consuming alcohol, rated the experience as less enjoyable, and reported more sedative and unpleasant effects compared to those on a placebo. Importantly, naltrexone did not alter how drunk people felt or their coordination. The intoxication was still there; the fun was not.²

A daily diary study tracking people in real-world drinking situations confirmed a similar picture. Those assigned to naltrexone reported lower levels of intense subjective response to alcohol, felt less impaired at the same levels of consumption, and drank less overall. The naltrexone group consumed roughly one fewer drink per session compared to placebo. Their craving didn’t change much, but the payoff from each drink shrank enough to slow them down naturally.³

You Will Not Get Violently Ill

Many people confuse naltrexone with disulfiram (sold as Antabuse), which is an entirely different drug with an entirely different mechanism. Disulfiram blocks the enzyme that metabolizes alcohol, so drinking on it causes nausea, vomiting, flushing, and a racing heart. The misery is the point: it creates a punishment response that discourages drinking. Naltrexone does nothing like this. There is no chemical buildup of toxic byproducts and no violent physical reaction. You can safely drink alcohol on naltrexone without winding up in the emergency room from the medication itself.

That said, “safely” deserves a caveat. Naltrexone can make the sedating side of alcohol more noticeable. When the euphoria is blunted, what remains is more of the drowsiness and the foggy, slightly nauseated feeling that people normally power through because they’re focused on the pleasurable side. Some people find that a few drinks on naltrexone leave them feeling sluggish or queasy simply because the rewarding mask has been pulled off, and what’s underneath isn’t that appealing. This is pharmacologically different from the severe reaction disulfiram causes, but it still means the experience may feel worse than expected.

The Sinclair Method and Drinking on Purpose

Here’s where naltrexone gets genuinely counterintuitive. One well-known treatment approach actually asks you to drink while taking it. The Sinclair Method, named after researcher John David Sinclair, is built on the idea that the most effective way to use naltrexone is to take it about an hour before you drink, then go ahead and drink. The logic is rooted in a learning principle: if you repeatedly perform a behavior and the expected reward doesn’t arrive, the drive to perform that behavior gradually fades. Sinclair called this pharmacological extinction.⁴

The key insight from Sinclair’s research was that naltrexone worked better when paired with actual drinking than when given during abstinence. This makes sense if you think of it as a learning process: your brain can only un-learn the connection between alcohol and pleasure if you actually drink and experience the blocked reward. Taking naltrexone on days you don’t drink doesn’t give the brain anything to un-learn. Sinclair proposed that people should take naltrexone only on days they intended to drink, continue this indefinitely, and let the gradual erosion of the reward drive do the heavy lifting.

A clinical trial testing a variation of this targeted approach found that men who took 50 mg of naltrexone specifically before high-risk drinking situations drank significantly less than those taking it daily or taking a placebo.⁵ The Sinclair Method remains somewhat controversial in mainstream addiction medicine, partly because it requires continued drinking (which many treatment programs philosophically oppose) and partly because the extinction process can take months. But the evidence that naltrexone is effective when paired with drinking, not just abstinence, is well supported.

How Naltrexone Compares to Other Alcohol Medications

Naltrexone is one of three FDA-approved medications for alcohol use disorder in the United States. The other two are acamprosate and disulfiram, and all three work through completely different mechanisms. Disulfiram makes drinking physically punishing. Acamprosate helps restore chemical balance in the brain after someone has stopped drinking, easing the anxiety and restlessness that come with early sobriety. Naltrexone occupies the middle ground by changing what drinking feels like without forcing abstinence or causing illness.

A head-to-head trial comparing all three medications found that disulfiram was more effective at reducing heavy drinking days and increasing abstinent days during the active treatment phase. However, once the medication period ended, the differences between disulfiram and the other two drugs narrowed. Naltrexone and acamprosate performed similarly to each other across most drinking measures.⁶ The practical takeaway is that naltrexone’s biggest advantage isn’t necessarily raw efficacy in clinical trials but rather its flexibility. It works whether your goal is total abstinence or reduced drinking, and it doesn’t require complete sobriety before starting.

What About Your Liver?

This is one of the most common concerns people raise, and the history behind it explains why. Naltrexone’s original FDA labeling carried a black-box warning about hepatotoxicity based on early studies that used very high doses (300 mg per day, six times the standard dose for alcohol use disorder). At the standard 50 mg dose, the liver risk looks very different.

A multicenter safety study of naltrexone in people being treated for alcohol dependence found that liver function test results in the naltrexone group were similar to those in a reference group not taking the drug.⁷ More recent data has been even more reassuring. A study that tracked liver enzymes before, during, and after naltrexone use found that average liver enzyme levels actually dropped after patients started the medication. This pattern held even among patients who already had liver disease or cirrhosis. The likely explanation is simple: people drank less on naltrexone, and less alcohol meant less liver damage. Severe liver enzyme elevations were rare, occurring at a rate of roughly one to two events per 1,000 patients per year.⁸

A separate study focused specifically on people with cirrhosis found that only about 2% experienced any liver enzyme elevation, and when those cases were reviewed, none met the criteria for drug-induced liver injury. No deaths or new complications were attributed to the medication.⁹ The old fear that naltrexone is inherently dangerous for the liver has not aged well. For most people, the risk from continued heavy drinking dwarfs any theoretical liver risk from the medication itself.

The Monthly Injection Option

Naltrexone also comes as an extended-release injectable (Vivitrol), given once a month as an intramuscular shot. The appeal is obvious: you don’t have to remember a daily pill, and you can’t skip a dose on the day you’re tempted to drink. The injection delivers a steady level of naltrexone for about four weeks.

Clinical trials of the injectable form have shown it reduces drinking days and increases abstinence rates compared to placebo. In one multicenter trial, participants receiving the naltrexone injection had significantly fewer drinking days and a higher abstinence rate (roughly 18% versus 10% in the placebo group). The injection also delayed the first drink after treatment began.¹⁰ Longer-acting formulations have shown particular benefit in reducing heavy drinking episodes among men.¹¹

If you drink while having Vivitrol in your system, the experience is the same as with the oral form: the opioid blockade is already in place, so alcohol’s rewarding effects are blunted continuously. There’s no “off switch” for the injection the way you could skip a pill. For people who struggle with the discipline of daily dosing, or who know they’d conveniently forget the pill on nights they want to drink freely, the injection removes that loophole.

Why Naltrexone Works Better for Some People

One of the frustrating realities of naltrexone is that it doesn’t work equally well for everyone. Some people report a dramatic shift in their drinking almost immediately; others barely notice a change. Genetics appears to be a significant piece of this puzzle.

A meta-analysis examining a specific variation in the mu-opioid receptor gene (known as the A118G polymorphism of OPRM1) found that naltrexone-treated patients carrying the G version of this gene had roughly twice the odds of avoiding relapse compared to those with only the A version.¹² The logic fits the mechanism: people whose opioid receptors are wired slightly differently may be more sensitive to having those receptors blocked, so naltrexone’s effect on their reward system is more pronounced.

More recent research has shown that the picture is more complicated than a single gene. Interactions between the OPRM1 gene and genes involved in dopamine signaling also shape the response. People with certain combinations of opioid and dopamine gene variants showed large treatment effects from naltrexone, while those with different combinations responded more modestly.¹³ Genetic testing to guide naltrexone prescribing isn’t standard practice yet, but the science is moving in that direction. If you try naltrexone and it seems to do very little, your genes may be part of the explanation rather than some failure of willpower.

Effects Beyond Alcohol

Because naltrexone blocks opioid receptors broadly, not just the ones involved in alcohol’s reward, it can affect the way your brain processes other pleasurable experiences too. This isn’t always dramatic, but some people notice it.

One area where this has been studied is smoking. Heavy drinkers who smoke often find that their cigarette cravings spike when they drink. A study of heavy drinking smokers found that naltrexone blunted cigarette craving during alcohol consumption compared to placebo.¹⁴ This makes sense because both nicotine and alcohol partially depend on endorphin and dopamine pathways to deliver their rewarding effects. Block the endorphin piece with naltrexone, and both substances lose some of their appeal.

Food cravings are another area of interest. A pilot study in obese women found that the connection between reward-driven eating tendencies and food craving intensity was significant on placebo days but disappeared on naltrexone days. In other words, people who were normally driven toward food for emotional or hedonic reasons experienced less of that pull when naltrexone was on board.¹⁵ Some people on naltrexone report that food tastes slightly less exciting, exercise feels a little less rewarding, or the “runner’s high” after a workout doesn’t quite arrive. These effects are generally mild and don’t bother most people, but they’re worth knowing about. You’re not losing the ability to feel pleasure; the volume is turned down slightly on endorphin-mediated rewards across the board.

What Naltrexone Cannot Do

Naltrexone will not prevent you from getting drunk. It blocks the opioid-mediated reward pathway, but alcohol also acts on GABA receptors, glutamate receptors, and other systems that produce intoxication. Your coordination will still suffer, your judgment will still be impaired, and you can still drink enough to put yourself in danger. Naltrexone does not act as a protective barrier against alcohol poisoning or drunk driving, and it would be dangerous to treat it as one.

It also won’t eliminate cravings entirely. The daily diary study mentioned earlier found that naltrexone affected how rewarding drinking felt but did not significantly reduce craving at the between-person level.³ You may still want a drink. The difference is that once you have one, it doesn’t deliver the same payoff, which over time can weaken the craving loop. But early on, the wanting can persist even as the liking fades. This mismatch trips up many people who expect naltrexone to function like an off switch for the desire to drink. It is more like a dimmer switch for the reward, and the wanting may take longer to catch up.

Naltrexone and Pregnancy

Evidence on naltrexone during pregnancy is limited, and most of the available data comes from its use in opioid use disorder rather than alcohol treatment specifically. A scoping review of alcohol pharmacotherapies in pregnancy noted that while some studies raised concerns about higher rates of certain pregnancy complications, naltrexone was generally considered a safer option compared to continued opioid agonist therapy or continued alcohol use during pregnancy.¹⁶ The situation is genuinely uncertain. If you are pregnant or planning to become pregnant and considering naltrexone for drinking, this is a conversation that needs to happen with your prescriber, because the risks of untreated heavy drinking during pregnancy are severe and well-documented, while the risks of naltrexone are poorly defined. It’s a judgment call that depends on individual circumstances, not a blanket yes or no.

The Opioid Blockade Warning

One practical consequence of naltrexone that catches people off guard has nothing to do with alcohol. Because naltrexone blocks all opioid receptors, it will also block opioid pain medications. If you are on naltrexone and need emergency surgery, break a bone, or experience severe pain, standard opioid painkillers like morphine, oxycodone, or fentanyl will not work normally. Higher doses to overcome the blockade are dangerous. Medical teams need to know you are on naltrexone so they can use non-opioid pain management strategies instead.

This matters doubly for the injectable form, which stays in your system for about a month. With oral naltrexone, the blockade fades within roughly 72 hours of your last dose. With Vivitrol, you’re carrying it around for weeks. Wearing a medical alert bracelet or carrying an information card isn’t overkill; it’s a sensible precaution if you’re on the injection and something unexpected happens.