Drink cherry concentrate in water, available through King Arthur Flour and elsewhere.
Basically cherries however you can get them.
You would have to drink a LOT of martinis to get enough, so maybe not that way.
Also, cherry pie filling works, but too much sugar.
No need to eat tart cherries, allopurinol works perfectly (no attacks in 15 years).
Tart cherries
As one who is debating taking Allopurinol, I looked into the successful studies with tart cherry juice, and the effective dose was 24 ounces a day.
Seemed to much for me to be able to follow successfully. I like variety in my fruits!