According to the MedicineNet.com, the liver is the only organ in the body that can rapidly replace damaged cells. However, there is no way of predicting how long it takes the liver to heal, since it depends on the nature and extent of the damage.
When liver damage is caused by excessive alcohol consumption and is diagnosed in the earliest, “fatty liver” stage, it can be reversed by at least six months of abstinence, explains the Princess Grace Hospital. The National Institutes of Health add that a drug-induced liver disease can also be reversed. On average, improvement is noticeable a week or two after discontinuation of the therapy. According to NIH, full recovery is usually observed two or three months after therapy withdrawal. The Cleveland Clinic Foundation explains that in the stage of hepatitis, damage may or may not be reversible, while in the stage of cirrhosis, damage is generally permanent.