Drug Classes: Diuretics

Used to treat: Hypertension, Edema due to CHF*

Mechanism of Action: Varies by specific variety (see below)

Contraindications: May cause cross sensitivity with sulfonamide or thiazide allergy, chronic electrolyte depletion, low potassium may increase risk of digoxin toxicity,



Pregnancy Category:

• B (Torsemide, Chlorthalidone, Hydrochlorothiazide, Indapamide, Metolazone) - Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women OR Animal studies have shown an adverse effect, but adequate and well-controlled studies in pregnant women have failed to demonstrate a risk to the fetus in any trimester.
• C (Chlorothiazide) - Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Common Medications (Brand -- Generic)


Loop Diuretics: Inhibit the reabsorption of sodium and chloride from the loop of Henle and distal renal tubule, causing water to follow via osmosis, increasing urinary output and decreasing blood pressure.

• Demadex - Torsemide*
• Tablets: 5mg, 10mg, 20mg, 100mg
• Injection: 10mg/ml

Thiazide Diuretics: Increase excretion of sodium and water in distal renal tubule, resulting in lowered blood pressure.

• Diuril - Chlorothiazide
• Tablets: 250mg, 500mg
• Oral Suspension: 250mg/5ml
• Thalitone - Chlorthalidone
• Tablets: 25mg, 50mg, 100mg
• Hydrodiuril, Oretic, Microzide - Hydrochlorothizide (HCTZ)
• Tablets: 25mg, 50mg
• Capsules: 12.5mg
• Oral Solution: 10mg/ml, 100mg/ml

Thiazide-like Diuretics: Increase excretion of sodium and water in distal renal tubule, resulting in lowered blood pressure.

• Lozol - Indapamide
• Tablets: 1.25mg, 2.5mg
• Zaroxolyn - Metolazone
• Tablets: 2.5mg, 5mg, 10mg

Common Side Effects

• Dehydration
• Low chloride levels
• Low potassium levels (supplementation may be required)
• Low magnesium levels
• Hyponatremia
• Metabolic alkalosis
• Hypovolemia
• Hyperurecima (frequent urination)

Combination Drugs Containing Diuretics:

• Tenoretic - Chorthalidone/ Atenolol (Beta Blocker)
• Clorpres - Chlorthalidone/ Clonidine (Centrally-acting Adrenergic)
• Tribenzor - HCTZ/ Olmesartan/ Amlodipine (Angiotensin Receptor Blocker/ Calcium Channel Blocker)
• HCTZ is available with just about every class of antihypertensive on the market

Miscellaneous

• Combination medications with diuretics in them often end in -oretic or -izide (eg. Tenormin, Tenoretic; Prinivil, Prinzide; Zestril, Zestoretic)
• Combination medications that don't lend themselves to adding -oretic or -izide to the name will simply call themselves by the non-combined name + HCT (eg. Diovan, Diovan HCT; Micardis, Micardis HCT)

Until next time,

C. Samuels