Frequent belching. What should i do now?

Hello! Sounds like your husband is having severe symptoms of gastroesophageal reflux disease (GERD) Please let him continue the antacids ( neksium) , i would recommend adding a prokinetic along with a with it. Losing weight really helps, if he is on the overweight side. Diet plays the most important role here. Avoid anything strongly acidic and with a high fat content and go in more for alkaline and watery food. Some of the food items which may trigger these symptoms - all your fried and spicy ( both pepper and chilli) food, pizza, cheese, chips, Chocolate, sodas, citric items and  most of the processed food products . Some of the food items you can eat are any whole grain food with high fibre content like oats, red/brown rice etc, sweet potatoes, nuts, bananas, melons etc. Anything strongly acidic is to be avoided. Smoking and alcohol - strictly NO. You had asked about milk, skimmed and low fat milk will help and act as a buffer but whole milk with high fat content will definitely make worsen the symptoms. However, with the diet modifications and medications, I still  suggest you to get an upper GI endoscopy to assess your esophagus and stomach and also check for h pylori infection, so treatment plan can be made based on the findings.

upper GI endoscopy