What is the starting dose of olmesartan (angiotensin II receptor antagonist) for adults with hypertension?

Olmesartan Starting Dose for Adult Hypertension

The starting dose of olmesartan for adults with hypertension is 20 mg once daily, which can be increased to 40 mg once daily after 2 weeks if additional blood pressure reduction is needed. 1

Standard Dosing Protocol

• Initial dose: 20 mg once daily when used as monotherapy in patients who are not volume-contracted 1
• Titration schedule: After 2 weeks of therapy, if blood pressure remains inadequately controlled, increase to 40 mg once daily 1
• Maximum dose: 40 mg once daily — doses above 40 mg do not appear to provide greater antihypertensive effect 1
• Dosing frequency: Once-daily dosing is recommended; twice-daily dosing offers no advantage over the same total dose given once daily 1

Special Considerations for Volume-Depleted Patients

For patients with possible intravascular volume depletion (e.g., those on diuretics, particularly with impaired renal function), consider a lower starting dose and initiate under close medical supervision. 1

• This precaution is critical to avoid excessive hypotension in volume-depleted states 1

Clinical Evidence Supporting This Dosing

The 20 mg starting dose is supported by robust clinical trial data:

• Olmesartan 20 mg once daily demonstrated superior efficacy compared to losartan 50 mg, valsartan 80 mg, and irbesartan 150 mg at their recommended starting doses in reducing diastolic blood pressure 2
• In Chinese patients with mild-to-moderate hypertension, olmesartan 20 mg showed significantly greater blood pressure reduction than losartan 50 mg after just 4 weeks (DBP reduction: 12.1 vs 7.2 mmHg, p<0.005) 3
• The 20 mg dose provides sustained 24-hour blood pressure control with trough-to-peak ratios above 50% 2
• In the OLMEBEST study of 823 German patients, olmesartan 20 mg achieved a 70% control rate and 76% response rate after 8 weeks, with mean reductions of 11.8 mmHg in diastolic BP and 17.1 mmHg in systolic BP 4

Monitoring and Follow-Up

• Blood pressure should be monitored regularly during dose titration to assess response 5
• Reassess at 2 weeks to determine if uptitration to 40 mg is needed 1
• If blood pressure remains uncontrolled on maximum dose (40 mg), add a second antihypertensive agent from a different class, preferably a thiazide diuretic or calcium channel blocker 5

Stage 2 Hypertension Exception

For patients with stage 2 hypertension (BP ≥140/90 mmHg with BP more than 20/10 mmHg above target), consider initial combination therapy with olmesartan plus another agent rather than monotherapy 5