Final answer:
Fluid intake with allopurinol should include drinking enough water and following a diet low in protein, nitrogen, and sodium intake, as well as avoiding oxalate-rich foods.
Step-by-step explanation:
When taking allopurinol, it is important to maintain a proper fluid intake to prevent kidney stone formation and gout flare-ups. Drinking enough water to make 2 to 2.5 liters of urine per day is recommended. Additionally, a diet low in protein, nitrogen, and sodium intake is advised, along with restriction of oxalate-rich foods such as chocolate, nuts, soybeans, rhubarb, and spinach.