This chapter examines the commonly prescribed drugs used for the treatment and management of some clinical conditions that alter the excretory functions of the kidneys. The pharmacological agents reviewed include those that affect water, sodium and glucose losses such diuretics, those that; alter the pH of the urine (alkalizing agents), for example sodium and potassium citrate, ammonium chloride, alkalizing agents, vasopressin receptor antagonists (aquaretic) and Sodium-Glucose Co-Transporters Inhibitors 2 (SGLTi2). These pharmacological agents are reviewed in relation to their pharmacokinetics, mechanism of action, clinical indications, contraindications, drug–drug interactions and unwanted effects. The clinical uses of these drugs are reviewed in the context of the management of what is termed, volume overload, hypertension and heart failure.