Answer: a. Sodium and potassium increases, calcium increases (1(e j..Ciuodnian unman iLe pod,* Urinary sodium, potassium and calcium increase in the first 24 hours of thiazide administration.* The acute effects of thiazide on Ca" excretion is variable:* It has been seen in various trials that urinary excretion increases in the initial stages of thiazide diuretic therapy. When administered chronically, thiazide diuretics decrease Ca" excretion.