Metabolic Alkalosis: This condition is characterized by an increase in bicarbonate (bicarb) levels and a decrease in chloride levels in the blood. It often results from excessive vomiting, which leads to the loss of hydrochloric acid, or from the use of diuretics that promote the excretion of chloride in the urine.

Chloride-Depleting Diuretics: The use of certain diuretics, especially those that act on the distal convoluted tubule like thiazides, can lead to increased bicarbonate reabsorption and decreased chloride reabsorption, resulting in metabolic alkalosis.
Excessive Bicarbonate Intake: Ingestion of large amounts of bicarbonate, either through antacids or baking soda, can directly increase bicarbonate levels in the blood.
Cushing's Syndrome: This condition, caused by excess cortisol, can lead to metabolic alkalosis due to the mineralocorticoid effects of cortisol, which promote sodium retention and potassium excretion, often accompanied by increased bicarbonate levels.

Hyperaldosteronism: A condition where the adrenal glands produce too much aldosterone, leading to sodium retention, potassium excretion, and metabolic alkalosis. Missing this diagnosis could lead to uncontrolled hypertension and its complications.
Milk-Alkali Syndrome: Characterized by hypercalcemia, metabolic alkalosis, and renal impairment, often due to excessive intake of calcium and alkali (such as in antacids). It's crucial not to miss this diagnosis due to its potential for severe renal damage.

Bartter Syndrome: A rare genetic disorder affecting the kidneys' ability to reabsorb sodium and chloride, leading to hypokalemia, metabolic alkalosis, and hypercalciuria. It's essential to consider this in the differential for young patients with unexplained metabolic alkalosis.
Gitelman Syndrome: Another rare genetic disorder that affects the kidneys' ability to reabsorb magnesium, sodium, and chloride, resulting in hypokalemia, hypomagnesemia, and metabolic alkalosis. It often presents later in life than Bartter Syndrome.