Hydrochlorothiazide: study card

Hydrochlorothiazide — Thiazide diuretic. Study the mechanism, listed uses and warnings from the US label on one sourced card.

Generic name: Hydrochlorothiazide
Class: Thiazide diuretic
Mechanism: Affects distal renal tubular electrolyte reabsorption and increases sodium and chloride excretion. The selected label describes the mechanism of its antihypertensive effect as unknown.
Used for: Hypertension, alone or with other antihypertensive medicines; Adjunctive treatment of edema associated with congestive heart failure or hepatic cirrhosis; Edema associated with specified forms of renal dysfunction
Common side effects: Orthostatic hypotension; Weakness; Nausea; Photosensitivity
Warnings: Contraindicated in anuria / sulfonamide allergy; Electrolyte imbalance (e.g., hypokalemia); May activate systemic lupus erythematosus
Interactions: Lithium (toxicity); Cholestyramine / colestipol; Antidiabetic drugs

Brand questions use only name pairings verified against the linked product source. Unverified pairings are withheld from these questions; the other study content remains available.

Drug class families: Thiazide and thiazide-like diuretics

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Label date: 20260826 · For learning, not clinical decisions. US label and brand information; always consult the current source.

Source snapshot checked: 2026-10-21. The source document and selected fields were compared. The complete card has not had an independent clinical review.

Practice

Pronunciation

Hydrochlorothiazide: hye-droe-klor-oh-THYE-a-zide

Pronunciation is shown for the US English generic name.

Other drugs in the same class

Thiazide and thiazide-like diuretics: Lisinopril / Hydrochlorothiazide, Losartan / Hydrochlorothiazide, Olmesartan / Amlodipine / Hydrochlorothiazide, Triamterene / Hydrochlorothiazide, Chlorthalidone

Body system

Cardiovascular · 47 Drug cards

Compare with related cards

Chlorthalidone

Same class family: Thiazide and thiazide-like diuretics

Mechanism: A long-acting oral diuretic that increases sodium and chloride excretion. Its site of action appears to be the cortical diluting segment of the ascending limb of Henle’s loop; the antihypertensive mechanism is not wholly clear.

On both cards: Common side effects — Nausea; Photosensitivity

Only on the Chlorthalidone card: Used for — Hypertension in adults · Common side effects — Dizziness; Headache; Rash · Warnings — Acute kidney injury; Hypokalemia, hyponatremia, hypomagnesemia; Anuria / sulfonamide allergy (contraindicated) · Interactions — Lithium; Insulin / oral hypoglycemics; Tubocurarine

Triamterene / Hydrochlorothiazide

Same class family: Thiazide and thiazide-like diuretics

Mechanism: HCTZ blocks renal tubular sodium and chloride reabsorption; triamterene inhibits distal sodium reabsorption, reducing potassium loss.

On both cards: Common side effects — Nausea

Only on the Triamterene / Hydrochlorothiazide card: Used for — Hypertension or edema with hypokalemia on HCTZ; Thiazide need where hypokalemia can't be risked · Common side effects — Dizziness; Headache; Fatigue; Dry mouth · Warnings — Hyperkalemia (contraindicated); Other potassium-conserving agents or supplements; Anuria / significant renal impairment · Interactions — Lithium; Other antihypertensives; Potassium supplements

Lisinopril / Hydrochlorothiazide

Same class family: Thiazide and thiazide-like diuretics

Mechanism: Lisinopril inhibits ACE, lowering angiotensin II and aldosterone; hydrochlorothiazide is a thiazide diuretic.

Only on the Lisinopril / Hydrochlorothiazide card: Used for — Hypertension when this fixed-dose combination is appropriate; it is not indicated for initial therapy · Common side effects — Dizziness; Headache; Cough; Fatigue; Orthostatic effects · Warnings — History of ACE inhibitor angioedema; Anuria / sulfonamide hypersensitivity; Contraindicated with sacubitril (neprilysin inhibitor) · Interactions — Diuretics (hypotension); NSAIDs incl. COX-2 inhibitors; Dual RAS blockade (ARBs, aliskiren)

An item counts as shared only when both cards use the same wording. If a card does not list an item, that is not a statement that the effect never occurs.