Brief Answer:
I'd recommend as follows...

Detailed Answer:
Hello there,
Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concerns...

It's a good thing that there are no new gout attacks in the past 6years.

However, he needs to check the serum Uric acid levels first. If the levels come within normal ranges, then he can discuss with his doctor regarding stoppage of the Allopurinol...Immediate stoppage is not recommended due to withdrawal signs, so it should be tapered off under the supervision of the treating doctor...

Since you're suspecting Allopurinol causing these stomach problems, you may consider another drug called Febuxostat, which works in a similar way to allopurinol but a lesser amount of side effects.

Please discuss this with his doctor and proceed further.

Meanwhile, for the stomach issues, he may continue the Protonix, also follow a few bits of suggestions as:

-Please try to go easy on the fatty/deep fried foods (better to avoid them completely for the time being).

-Certain food products are notorious for causing gas and bloating which in turn can give rise to such abdominal aches. These include high-fat dairy products, cheese, broccoli, cabbage, cauliflower, lentils, kidney beans, and chickpeas primarily. Please avoid them.

-Have brown/multigrain bread instead of regular white bread.

-Try to have fish, fish products, chicken and avoid red meat for the time being. Avoid alcohol (if at all consume)...

-Have plenty of fresh green vegetables, simple homemade foods, salads, yoghurt/curd based diet, avoid any form of spicy food...

-Eat in small portions but at regular intervals (have 4-5 small meals a day rather than having 2-3 large meals)...never skip breakfast and always have some healthy foods in breakfast (eg. some baked slices of brown/multigrain bread, boiled eggs, oats, yoghurt, muesli etc.)...

Let me know if I can assist you further...

Take Care
Kind Regards

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