If I have been taking allopurinol regularly, can I gradually stop taking it if I make physician?

Allopurinol is a medicine that is taken regularly to prevent future acute gout attacks and to prevent the condition becoming chronic. It works by lowering uric acid levels in your blood and thus preventing uric acid crystals forming in your joints.
Do not stop taking allopurinol without talking with your doctor first as stopping can bring on an attack of gout. Sticking with your treatment plan is the best way to prevent future attacks.

Adopting healthy lifestyle habits is a key part of an effective gout treatment plan. Eating a healthy diet, engaging in regular physical activity and losing weight if needed can lower your risk of repeated gout attacks, as well as the chances of developing heart disease, which is common in people with gout.

For more information see: https://www.drugs.com/health-guide/gout.html