• C03A Low-ceiling diuretics, thiazides 1 medications
• C03B Low-ceiling diuretics, excl. thiazides 12 medications
• C03C High-ceiling diuretics 21 medications
• C03D Potassium-sparing agents 16 medications
• C03E Diuretics and potassium-sparing agents in combination 7 medications
• C03X Other diuretics 3 medications