Alcoholism is a mental health problem which the person concerned cannot handle alone, usually. You seem to have understood the importance of medication in dealing with your husband's condition. It also appears that the prescribed medicine is not providing the expected results. Under these circumstances, I would suggest you to go in for a fresh assessment of his present condition in a hospital which has a psychiatric department with a functional de-addiction facility. Recovery from alcoholism usually takes a lot of commitments from the patient and the caregivers. A psychiatrist may be able to put your husband through de-addiction therapy which may show excellent initial results. However, my experience so far shows that in many cases the follow up treatment which includes medication, counselling etc. that may be required at times for more than a year, does not get complied with, mostly due to the reducing commitment and understanding of the people closely related to the patient.
Next Steps
Please get your husband treated in the de-addiction facility of a well-organised psychiatry department of a good hospital and follow the instructions from the doctors meticulously. Please do not allow any close relatives or friends who do not understand alcoholism as a disease that needs fully committed treatment and wholehearted support of close people, to involve in the treatment process and decisions connected with the treatment.