I'm sorry to hear about the trouble you and your family is going through. Alcohol dependence is something that requires comprehensive combined management through medicines and psychotherapy. With optimal management, the patient's will power can be gradually restored, while ensuring that he doesn't suffer from any alcohol withdrawal effects. Another thing to consider is the physical damage to the body due to frequent alcohol use, which also requires detailed evaluation.
Overall, it is important to note that medicines alone will not solve the problem in the long run . It has to be a combined approach. I advise you to see a psychiatrist for a detailed evaluation of your father, and initiation of combined medical and psychotherapeutic management.