Three medications are FDA-approved specifically to help people stop or reduce drinking: naltrexone, acamprosate, and disulfiram. A fourth option, topiramate, is commonly prescribed off-label with solid clinical evidence behind it. Each works through a different mechanism, and the right choice depends on whether you’re aiming for complete abstinence, gradual reduction, or relapse prevention after you’ve already quit.
Naltrexone: Reducing the Urge to Drink
Naltrexone blocks the brain’s opioid receptors, which are part of the reward system that makes alcohol feel pleasurable. When you drink on naltrexone, you don’t get the same buzz or reinforcement. Over time, this weakens the learned association between drinking and feeling good. Lab studies show it reduces cue-induced craving, slows the rate of consumption, and shortens drinking sessions compared to a placebo.
The standard dose is 50 mg daily in pill form, though a monthly injection is also available for people who have trouble remembering daily pills. Treatment should last at least three to four months. If you achieve full abstinence during that time, your prescriber may stop the medication and monitor you monthly for the next four to six months. If heavy drinking episodes continue, a longer or even indefinite course of treatment is often recommended.
Some people take naltrexone only on days when they anticipate drinking rather than every day. This “targeted” approach has clinical support and is sometimes called the Sinclair Method. The idea is to take the pill an hour or so before you expect to drink, so the opioid receptors are blocked during the drinking session. Some prescribers combine a lower daily dose with an extra targeted dose before high-risk situations.
Naltrexone is generally well tolerated. Nausea is the most common complaint, especially in the first week or two. Headache and fatigue also occur. Because the medication is processed by the liver, your prescriber will check liver enzymes before starting and periodically during treatment. Significant enzyme elevations are uncommon, occurring in roughly 1% of patients, and they reverse once the medication is stopped. One critical safety note: naltrexone blocks opioid receptors, so it will trigger immediate withdrawal in anyone currently using opioid painkillers or other opioids. You need to be opioid-free before starting it.
Acamprosate: Calming the Brain After Quitting
Acamprosate works on a completely different system than naltrexone. Heavy, long-term drinking throws off the balance between two brain signaling systems: one that excites nerve cells (glutamate) and one that calms them (GABA). When you stop drinking, the excitatory system stays ramped up, producing the anxiety, irritability, restlessness, and insomnia that make early sobriety so difficult. These symptoms can persist for weeks or months after acute withdrawal ends, and they are a major driver of relapse.
Acamprosate helps restore that balance by lowering excess glutamate activity and indirectly supporting the calming system. It also appears to boost the body’s natural endorphins in people with very high alcohol intake. The net effect is that the persistent discomfort of early sobriety becomes more manageable. A meta-analysis found that for every eight people treated with acamprosate for six to twelve months, one additional person maintained abstinence who would not have on placebo.
The medication is taken as two pills, three times a day, which can be inconvenient. It’s designed for people who have already stopped drinking, not for those trying to cut back while still actively consuming alcohol. The most common side effect is diarrhea. Unlike naltrexone, acamprosate is not processed by the liver, making it a better fit for people with liver disease, which is common among heavy drinkers.
Disulfiram: Deterrence Through Consequences
Disulfiram, the oldest of the three approved medications, takes a fundamentally different approach. It doesn’t reduce cravings or restore brain chemistry. Instead, it makes drinking physically unpleasant. The medication blocks an enzyme your liver uses to break down acetaldehyde, a toxic byproduct of alcohol metabolism. Normally, acetaldehyde is quickly converted to a harmless substance. With disulfiram on board, it accumulates rapidly.
If you drink while taking disulfiram, you’ll experience flushing, nausea, palpitations, sweating, dizziness, and a drop in blood pressure. The reaction is unpleasant enough that most people learn to avoid alcohol entirely. This makes it a purely psychological deterrent: it works best when you’re already motivated to stay sober and want an extra guardrail to prevent impulsive drinking.
The main limitation is adherence. If you simply stop taking the pill, you can drink again within a few days. For this reason, disulfiram tends to work best when someone else (a partner, family member, or clinic) observes you taking it. It’s not appropriate for people who might drink through the reaction, as severe cases can cause dangerous drops in blood pressure.
Topiramate: An Off-Label Alternative
Topiramate is FDA-approved for epilepsy and migraine prevention, but it has strong evidence for reducing alcohol consumption. A meta-analysis of seven trials with over 1,100 participants found that people taking topiramate had higher rates of abstinence and lower rates of heavy drinking compared to placebo.
The medication is started at a low dose and slowly increased over about eight weeks. This gradual ramp-up helps minimize side effects, which can include tingling in the hands and feet, difficulty concentrating or finding words, reduced appetite, and weight loss. Some people actually welcome the appetite suppression, since heavy drinkers often gain weight during recovery when they replace alcohol calories with food. Topiramate may be a good option if you’ve tried naltrexone or acamprosate without success, or if you have other conditions like migraines that topiramate could treat simultaneously.
Choosing Between Medications
Your goal matters when picking a medication. If you want to gradually reduce your drinking rather than quit cold turkey, naltrexone is the strongest fit because it works while you’re still drinking. If you’ve already stopped and want to protect your sobriety, acamprosate addresses the lingering anxiety and sleep disruption that pull people back. If you need a hard stop and have strong motivation, disulfiram provides a concrete consequence for slipping.
Your medical history also narrows the field. Liver problems point toward acamprosate. Current or recent opioid use rules out naltrexone. Kidney problems rule out acamprosate. Some prescribers combine naltrexone and acamprosate together, since they target different mechanisms.
How Long Treatment Typically Lasts
Most clinical guidelines recommend a minimum of three to four months on medication. That’s enough time to establish new habits and get past the period of highest relapse risk. But the data also shows that many people relapse within months to a year after stopping medication, so longer courses are common. Some people stay on naltrexone or acamprosate for a year or more, particularly if they’ve had previous relapses.
Monthly check-ins during treatment are standard, both to monitor side effects and to assess whether the medication is working. If you stop the medication after a period of abstinence, continued monthly monitoring for four to six months helps catch early signs of relapse before it escalates.
Medication Works Better With Support
These medications address the biological side of alcohol dependence, but drinking is also tied to habits, stress patterns, social environments, and emotional triggers. Combining medication with some form of behavioral support, whether that’s cognitive behavioral therapy, a recovery group, or structured counseling, addresses both sides. Naltrexone in particular pairs well with strategies like pacing your drinks and identifying high-risk situations, since it makes those strategies easier to execute by dampening the craving that overrides good intentions.
None of these medications require you to white-knuckle your way through recovery. They’re designed to make the process more manageable by changing the brain chemistry that drives compulsive drinking. The fact that most people with alcohol problems never try medication, even though it roughly doubles the odds of success in clinical trials, is one of the bigger gaps in how alcohol use disorder is currently treated.