Acamprosate is a prescription medication used to help people with alcohol use disorder stay sober after they’ve stopped drinking. It works by restoring the chemical balance in the brain that heavy, prolonged alcohol use disrupts, which helps reduce the persistent cravings and emotional discomfort that make early sobriety so difficult. It’s sold under the brand name Campral and is one of three FDA-approved medications for alcohol use disorder.
How Acamprosate Works in the Brain
Chronic heavy drinking reshapes your brain chemistry. Over time, the brain adapts to the constant presence of alcohol by ramping up certain excitatory signals and dampening calming ones. When you stop drinking, this imbalance doesn’t correct itself overnight. The result is a prolonged state of restlessness, anxiety, sleep disruption, and cravings that can persist for weeks or months after the last drink.
Acamprosate helps normalize that excitatory-calming imbalance. It doesn’t produce a “high,” it doesn’t make you feel sedated, and it doesn’t cause a negative reaction if you drink alcohol. Instead, it quietly works in the background to ease the neurological turbulence of early recovery. Think of it as helping your brain recalibrate to functioning without alcohol.
When to Start Taking It
Acamprosate works best in people who have already stopped drinking for three to four days before starting the medication. It’s not used during active withdrawal. The typical approach is to begin treatment as soon as possible after the withdrawal period ends, once you’ve achieved initial abstinence. It should be part of a broader treatment plan that includes counseling or a support program.
One important point: if you relapse while taking acamprosate, you should keep taking it. The FDA labeling specifically notes that treatment should be maintained even if a relapse occurs. A slip doesn’t mean the medication has failed, and continuing it can help you get back on track.
Standard Dosing Schedule
The standard adult dose is two 333 mg tablets taken three times a day, for a total of six tablets daily. That three-times-a-day schedule is one of the medication’s practical drawbacks, since it requires more consistency than a once-daily pill. Many people tie doses to meals (breakfast, lunch, dinner) to build the habit. If you miss a dose, take it as soon as you remember, but if it’s close to time for the next one, just skip ahead and stay on schedule. Don’t double up.
People with moderate kidney problems take a reduced dose of one tablet three times daily. Acamprosate is completely off the table for anyone with severe kidney impairment, defined as a creatinine clearance below 30 mL per minute, because the kidneys are responsible for clearing the drug from the body.
Why It’s Preferred for Certain People
Acamprosate has several characteristics that make it the better choice for specific patient profiles, particularly when compared to naltrexone, the other widely used medication for alcohol use disorder.
- Liver disease: Unlike naltrexone, acamprosate is not processed by the liver at all. This makes it the go-to option for people with liver damage, which is common among heavy drinkers. For people with significant liver compromise, it’s typically the first choice.
- Opioid use: Naltrexone blocks opioid receptors, so it can’t be used by anyone taking opioid medications (including those on methadone or buprenorphine for opioid addiction). Acamprosate has no such conflict.
- Pregnancy: Acamprosate may be preferred during pregnancy because opioid medications are sometimes needed around delivery, which would conflict with naltrexone.
- Multiple medications: Because acamprosate doesn’t interact with alcohol and carries no boxed warning (the FDA’s most serious safety alert), it tends to be a good fit for people who are already taking several other medications or who are using other substances.
Side Effects
Acamprosate is generally well tolerated. The most commonly reported side effect is diarrhea, which tends to be mild and often improves as your body adjusts to the medication. Some people also experience nausea, gas, headache, or insomnia, but severe adverse reactions are uncommon. The absence of an FDA boxed warning reflects its relatively favorable safety profile compared to other options in its class.
How Long Treatment Lasts
There’s no fixed stopping point written into the guidelines. Treatment duration varies by individual, but clinical trials typically studied acamprosate over periods of three to twelve months. The general principle is to continue as long as the medication is helping you maintain sobriety and you’re engaged in a broader recovery plan. Stopping too early, particularly in the first year when relapse risk is highest, may undermine the stability you’ve built. Your prescriber will help determine the right timeline based on how your recovery is going.
Acamprosate won’t do the work alone. It’s designed as one component of a comprehensive approach that includes therapy, support groups, or other psychosocial treatment. The medication reduces the neurological pull toward alcohol; the behavioral work helps you build the life that keeps you from going back.