Alcohol Use Disorder (AUD) is very common and can lead to medical, occupational, social and legal impairments for affected individuals and their families. Despite the high prevalence of AUD and its significant public health consequences, patients with this disorder continue to be under-identified and undertreated. The American Psychiatric Association has recently come out with practice guidelines for the pharmacological treatment of AUD. “This new guideline is an important step in bringing effective, evidence-based treatments for alcohol use disorder to many more people and in helping address the public health burden of alcohol use”, APA President Anita Everett, M.D., said in a press release.
The guideline reviews the rationale for use and possible side effects for 5 medications that have been shown to be effective for the treatment of AUD: naltrexone, acamprosate, disulfiram, gabapentin, and topiramate. These treatments are meant as part of an interdisciplinary approach to the treatment of substance abuse, not as a substitute.
Naltrexone is an opioid antagonist. It is found to be more helpful in people who are still drinking versus people who are already abstaining from alcohol. It works to extinguish drinking by removing the positive reinforcement effects to alcohol on the brain. Studies have shown that it can help prevent the development of severe alcohol use disorder. It does not necessarily help on its own to achieve abstinence from alcohol, but even reduction of heavy drinking can reduce some of the major negative effects of alcohol use, including medical and occupational effects. Studies have shown that it is effective in reducing and preventing relapses into heavy drinking. It can be particularly helpful in people who have high cravings for alcohol. A typical dose of oral naltrexone is 25 mg bid. A once-monthly, extended-release injectable formulation (Vivitrol) is available as well and is typically dosed at 380 mg qmonth. Common side effects include diarrhea and abdominal cramping. There is an FDA black box warning about the potential for liver damage, but further research has shown that this is a rare side effect and occurred only in patients who were given a higher-than-recommended dose. Still, some physicians elect to check baseline LFTs and monitor them periodically. It is important to avoid using opioid medications while taking naltrexone.
Acamprosate is approved by the FDA for treatment for alcohol dependence with other supportive therapies. Studies have shown it to be helpful in both reduced consumption of as well as maintaining abstinence from alcohol. Its mechanism of action is still under study. Common side effects include diarrhea, headaches, insomnia and impotence. Less common but more serious side effects include irregular heart rate and effects on blood pressure. Acamprosate is cleared renally so it should be avoided in patients with significant renal impairment.
Disulfiram works by producing an acute sensitivity to alcohol consumption by inhibiting acetaldehyde dehydrogenase. With disulfiram on board, 5-10 minutes after alcohol consumption, the patient will experience “hangover” symptoms for the next 30 minutes to several hours. These symptoms include flushing of the skin, accelerated heart rate, shortness of breath, nausea, vomiting, headache and mental confusion. Typically the regimen is initiated by prescribing 500mg qday x 1-2weeks then the maintenance dose is 125-500mg qday until the patient has fully abstained from alcohol. There is no tolerance to disulfiram – the longer it is taken, the stronger its effects. The main drawback is that the patient has to be motivated to take the medication consistently. The medication does not decrease craving for alcohol, so it is important that it be used in conjunction with supportive therapy and motivational interviewing. Common side effects include headache and metallic taste in mouth. It should not be taken within 12 hours of drinking alcohol and its effects can last for up to 2 weeks.
Naltrexone and acamprosate have the best evidence backing their use in treating AUD. Disulfiram can be helpful if a patient is seeking abstinence and is motivated. Topiramate and gabapentin can be considered alternative treatment options. Gabapentin dosed at 300 mg tid has been found to be helpful to reduce withdrawal effects, including tremors, anxiety, and seizures, when a person is reducing his alcohol consumption. More studies need to be conducted to assess their effectiveness in AUD, but generally the concern is that there is a higher risk of problematic side effects with these two medications compared to naltrexone and acamprosate. Patients taking topiramate are at an increased risk of cognitive dysfunction, dizziness and loss of appetite, whereas patients taking gabapentin may experience fatigue, insomnia, and headache.
Gabapentin and carefully monitored benzodiazepine tapers play a role during the detoxification phase of abstinence from alcohol. This to help patients avoid withdrawal symptoms which include worsening anxiety, tremors, diarrhea and nausea. Serious withdrawal effects include seizures and confusion. It is important to remember that both alcohol intoxication and withdrawal can be life-threatening.
The full practice guideline is included here as a reference for those who are interested in more detailed information.
Pharmacological treatment is an important part of the interdisciplinary approach to effectively treating AUD and reducing its negative outcomes.