Nalmefene: What It Is and How It Helps

Nalmefene is a medication used to help adults reduce heavy drinking. It works on brain receptors tied to reward and craving, making it easier to cut back when combined with support. Doctors usually offer it to people who drink heavily and want to reduce consumption, not necessarily to those aiming for total abstinence.

How it works and who it's for

Nalmefene blocks opioid receptors that play a role in the pleasure from alcohol. When those receptors are less active, drinking becomes less rewarding and urges often drop. Think of it as a tool that blunts the reward signal so other strategies and counseling have more effect.

Nalmefene is meant for adults with alcohol dependence who have a high drinking risk and no immediate medical reasons to stop drinking right away. It is not for people using opioids or those in active opioid withdrawal — nalmefene can cause sudden, severe withdrawal symptoms. Tell your doctor about pain meds, opioid prescriptions, or recent opioid use.

Use, safety, and practical tips

The common tablet dose is 18 mg. People typically take nalmefene on days they feel at risk of drinking or as prescribed by a clinician. Doctors check progress after a few weeks to decide if continuing helps. Always follow your prescriber's instructions and keep regular appointments.

Common side effects include nausea, dizziness, trouble sleeping, and headache. Most side effects are mild and appear early. If you feel faint, have severe dizziness, signs of liver problems, or mood changes, contact your healthcare provider right away. Pregnant or breastfeeding people should avoid nalmefene.

Do not mix nalmefene with opioid painkillers or opioid-based cough medicines. Combining nalmefene with other drugs that affect mood may need monitoring. If you take antidepressants, antipsychotics, or strong pain medicines, tell your clinician so they can adjust care safely.

Pair nalmefene with counseling, support groups, or structured alcohol reduction programs — medication works best with help. Keep a drinking diary to track progress and side effects. If you slip and have a heavy drinking day, don’t stop the treatment plan without checking with your provider.

Regulatory status varies by country. In Europe nalmefene is approved for reducing alcohol consumption in adults with high drinking risk; in the United States it’s not prescribed for this use. Your doctor can explain availability, cost, and whether your health plan covers it. Expect liver tests before and during treatment if you have liver disease. If cost or access is an issue, ask about support programs or alternative medicines your clinician recommend.

Ask how nalmefene fits your goals, what to expect in the first month, and how long to try it before deciding if it works. Also ask about other options like naltrexone, which works similarly but may suit some people better. If you want to cut back on alcohol and are open to medication plus support, nalmefene is worth discussing with your doctor.