There is growing evidence that ketamine can be useful in treating excessive drinking. Most people who drink too much and would like to reduce it took a long time to get that way. Many are stuck in a pattern of attempting abstinence alternating with binging. Ketamine may help to oppose the changes in the brain which maintain this pattern.
In recent years a number of researchers have concluded that addiction to alcohol, opioids, cocaine, and amphetamines involves changes in parts of the brain that are termed the reward center. These changes in turn affect behavior by altering the physiology of the parts of the brain which involve planning, decision making, and evaluating. These changes make overcoming addiction of any sort with simple willpower nearly impossible. It is precisely your willpower which is undermined in the process. The decision making parts of your brain are altered in a way that resolutions like "I will just say no" becomes more like "I will say no tomorrow, but just now I am going to have a drink". When I was a chain smoker I would resolve (once again) to stop smoking and five minutes later light up a cigarette. I did finally quit, but it was not easy, and involved overcoming precisely the kind of changes referred to above. Lucky for me the reward center effects of nicotine are nowhere near as powerful as many other drugs.
There are studies which support the idea that ketamine helps increase neural plasticity, allowing the harmful connection patterns involved in addiction to be undone. It is a sort of start over our reset function.