What is the recommended initial dose and titration schedule of losartan for hypertension in adults, including adjustments for elderly patients and those with moderate renal impairment?

Losartan Dosing for Hypertension

For adults with hypertension, start losartan at 50 mg once daily and titrate to 100 mg once daily after 2–4 weeks if blood pressure remains ≥140/90 mmHg; this represents the maximum effective dose for blood pressure control. 1

Initial Dosing and Titration

• Begin with losartan 50 mg once daily, which can be taken at any convenient time of day to establish a habitual pattern and improve adherence. 2, 1
• Re-evaluate blood pressure every 2–4 weeks during titration, aiming to reach target BP (<130/80 mmHg for most patients, minimum <140/90 mmHg) within 3 months of therapy initiation. 2, 1
• Increase to 100 mg once daily if office or home blood pressure remains ≥140/90 mmHg after 2–4 weeks on the initial dose; this provides near-maximal antihypertensive effect. 1, 3
• Doses above 100 mg daily do not provide additional blood pressure reduction in hypertension, though 150 mg daily may be used in heart failure with reduced ejection fraction. 1, 3

Combination Therapy Strategy

• Most patients with confirmed hypertension (BP ≥140/90 mmHg) should receive combination therapy as initial treatment rather than monotherapy, preferably combining losartan with either a dihydropyridine calcium channel blocker (e.g., amlodipine 5–10 mg) or a thiazide-like diuretic (e.g., chlorthalidone 12.5–25 mg or hydrochlorothiazide 12.5–25 mg). 2
• Fixed-dose single-pill combinations are strongly recommended when using dual therapy, as they significantly improve medication adherence and persistence. 2, 1
• If blood pressure remains uncontrolled on losartan 100 mg plus one other agent, escalate to triple therapy by adding the third drug class (ARB + calcium channel blocker + thiazide diuretic), preferably as a single-pill combination. 2

Special Populations

Elderly Patients (≥65 years)

• Start with losartan 50 mg once daily in elderly patients; no routine dose reduction is required based on age alone. 1, 4
• Titrate more gradually (every 2–4 weeks rather than weekly) in patients ≥85 years or those who are frail, monitoring closely for symptomatic hypotension and orthostatic changes. 1, 3
• Measure blood pressure in both sitting and standing positions (after 5 minutes seated, then at 1 and 3 minutes after standing) to detect orthostatic hypotension before initiating or intensifying therapy. 2, 1
• Continue lifelong antihypertensive treatment even beyond age 85 if well tolerated, as discontinuation increases cardiovascular risk. 2, 3

Moderate Renal Impairment (eGFR 30–60 mL/min/1.73 m²)

• No dosage adjustment is required for patients with mild to moderate renal impairment (eGFR >30 mL/min/1.73 m²). 1, 5, 6
• Start with losartan 50 mg once daily and titrate to 100 mg as needed based on blood pressure response. 6
• Check serum creatinine/eGFR and potassium within 1–2 weeks after initiating therapy or increasing doses, then monitor at least annually during maintenance. 1
• Losartan is not removed by hemodialysis; patients on dialysis can receive standard dosing (50–100 mg daily). 5, 6

Hepatic Impairment

• Reduce the starting dose to 25 mg once daily in patients with hepatic impairment, as losartan plasma concentrations increase approximately 5-fold in this population. 1

Monitoring and Safety

• Check serum potassium and creatinine within 1–2 weeks after starting losartan or changing doses, especially in patients with diabetes, chronic kidney disease, or those taking other potassium-sparing agents. 1
• Monitor blood pressure at 2–4 week intervals using validated automated devices with appropriately sized cuffs until target is achieved. 1
• Home blood pressure monitoring is strongly advised; a home reading ≥135/85 mmHg corresponds to office hypertension ≥140/90 mmHg. 1

Critical Safety Considerations

• Never combine losartan with an ACE inhibitor or direct renin inhibitor (aliskiren), as dual renin-angiotensin system blockade increases the risk of hyperkalemia, syncope, and acute kidney injury without providing additional cardiovascular benefit. 2, 1
• Losartan is absolutely contraindicated throughout pregnancy due to serious fetal toxicity (renal dysfunction, oligohydramnios, skull hypoplasia, fetal death); discontinue immediately upon pregnancy detection. 1
• The risk of first-dose hypotension is low with losartan compared to ACE inhibitors, and no special precautions are needed for initial dosing. 4

Common Pitfalls to Avoid

• Do not delay treatment intensification when blood pressure remains ≥140/90 mmHg; prompt action within 2–4 weeks is required to reduce cardiovascular risk. 1
• Do not rely on monotherapy dose escalation alone; combination therapy with agents from different classes is more effective than maximizing a single drug. 2, 1
• Do not assume treatment failure without first confirming medication adherence and excluding secondary causes of hypertension or interfering substances (NSAIDs, decongestants, oral contraceptives, systemic corticosteroids). 1
• Do not add a beta-blocker as second- or third-line therapy unless there are compelling indications (angina, post-MI, heart failure with reduced ejection fraction, atrial fibrillation), as beta-blockers are less effective than calcium channel blockers or diuretics for stroke prevention. 2, 1