Hydrochlorothiazide + Losartan Potassium

Hydrochlorothiazide + Losartan Potassium is a combination medicine that helps control high blood pressure. Losartan is an angiotensin II receptor antagonist (ARB) that relaxes blood vessels, allowing blood to flow more smoothly and the heart to pump more efficiently. Hydrochlorothiazide is a diuretic that removes extra water and electrolytes from the body. This combination is effective for treating hypertension and is also indicated to reduce the risk of stroke in patients with hypertension and left ventricular hypertrophy.

• Hypertension (high blood pressure)
• Reduction of stroke risk in patients with hypertension and left ventricular hypertrophy

Adult Dose (Oral):

• Hypertension: Initial: 50 mg/12.5 mg once daily; may increase to 100 mg/25 mg if needed
• Severe Hypertension: Starting dose: 50/12.5 once daily; may increase to 100/25 after 2-4 weeks if needed
• Hypertension with LVH: Initial: 50/12.5; may increase to 100/12.5, then 100/25 if needed; Max: 100/25 once daily
• Volume Depletion: Start with losartan 25 mg once daily
• Elderly: Initial dose 50/12.5; Max 100/25 should not be used as initial therapy

Renal Dose: CrCl >30 mL/min: No dosage adjustment; not recommended in severe renal impairment

Common Side Effects:

• Dizziness
• Nausea
• Taste change
• Upset stomach
• Diarrhea
• Headache
• Weakness
• Decreased blood pressure
• Glucose intolerance
• Increased blood uric acid
• Electrolyte imbalance

Others: Vertigo, angioedema, hyperkalemia, gastrointestinal disturbances, angina, palpitation, dyspnea, hepatitis, atrial fibrillation, syncope, pancreatitis, cough, erectile dysfunction, renal impairment

Precautions:

• Hydrochlorothiazide + Losartan may decrease alertness, affect vision or make you feel sleepy and dizzy; do not drive if these symptoms occur
• May cause dehydration; drink plenty of fluids; inform doctor if extreme thirst, very dry mouth or muscle weakness develops
• May cause dizziness; get up slowly when rising from a sitting or lying position
• Not safe during pregnancy and breastfeeding
• Angioedema: caution
• Periodic determination of serum electrolytes
• Hypokalemia may rarely develop; with severe cirrhosis or after prolonged therapy
• Renal impairment and symptomatic hypotension

Contraindications:

• Hypersensitivity
• Anuria
• Hypersensitivity to sulfonamide-derived drugs
• Pregnancy
• Intravascular volume depletion

Drug Interactions:

• Reduced excretion of lithium
• NSAIDs (including selective COX-2 inhibitors): May reduce diuretic, natriuretic & other antihypertensive effects
• Do not co-administer with aliskiren in patients with diabetes & renal impairment
• Potassium-sparing diuretics, potassium supplements or salt substitutes containing potassium: Increased serum potassium
• Alcohol, Barbiturates: May potentiate orthostatic hypotension
• Antidiabetic drugs: Dosage adjustment may be required
• Cholestyramine & Colestipol: Reduced absorption

Food Interactions: Hydrochlorothiazide + Losartan may cause excessive drowsiness with alcohol.

Use in Pregnancy: Unsafe during pregnancy; angiotensin-II receptor antagonists should be avoided in pregnancy; may adversely affect fetal and neonatal blood pressure control and renal function; contraindicated in pregnancy.

Use in Lactation: Information on use of angiotensin-II receptor antagonists in breastfeeding is limited; not recommended in breastfeeding.

Renal Impairment: CrCl >30 mL/min: Follow usual regimen of 50/12.5; loop diuretics preferred in severe renal impairment; hydrochlorothiazide is not recommended.

Hepatic Impairment: Not recommended for titration in hepatic impairment (appropriate 25 mg starting dose of losartan cannot be given).

Overdose: Losartan: Hypotension and tachycardia; bradycardia may occur; not removed by hemodialysis. Hydrochlorothiazide: Electrolyte depletion (hypokalemia, hypochloremia) and dehydration; hypokalemia with digitalis may accentuate cardiac arrhythmias; symptomatic treatment.