Onset and Duration of Telmisartan's Blood Pressure-Lowering Effect
Telmisartan begins to lower blood pressure within 3 hours of the first dose, with maximal blood pressure reduction achieved by approximately 4 weeks of once-daily therapy. 1
Initial Blood Pressure Response
- Blood pressure reduction is detectable after the first dose, with onset of antihypertensive activity occurring within 3 hours of oral administration 1
- The magnitude of initial blood pressure reduction is dose-dependent, with typical reductions (after placebo subtraction) of approximately 6-8/6 mmHg for 20 mg, 9-13/6-8 mmHg for 40 mg, and 12-13/7-8 mmHg for 80 mg 1
- Maximum blood pressure reduction occurs by approximately 4 weeks of continuous once-daily dosing 1
Sustained 24-Hour Blood Pressure Control
- Telmisartan maintains effective blood pressure reduction throughout the entire 24-hour dosing interval, with trough-to-peak ratios of 70-100% for both systolic and diastolic blood pressure at doses of 40-80 mg 1
- The long elimination half-life of approximately 24 hours ensures sustained blood pressure control, including during the critical last 6 hours of the dosing interval (2:00 AM to 8:00 AM) 2, 3
- Blood pressure control is maintained even in patients who previously failed to respond to other antihypertensive medications 4
Long-Term Efficacy and Offset
- Long-term studies demonstrate that the antihypertensive effect is maintained for at least one year of continuous treatment 1
- Upon cessation of telmisartan therapy, blood pressure gradually returns to baseline values over a period of several days to one week, indicating no rebound hypertension 1
- The consistent 24-hour blood pressure control and lack of tolerance development make telmisartan suitable for long-term management 3
Clinical Monitoring Recommendations
- Follow-up assessment should occur at 1-3 months (preferably 1 month) to evaluate both tolerance and full blood pressure-lowering effect 5
- The usual dose range is 20-80 mg once daily, with doses up to 160 mg not appearing to cause further blood pressure decrease 6, 1
- Monitoring of kidney function and serum potassium levels is recommended, as with all RAS blockers 7
Important Clinical Considerations
- Response rates are lower in Black patients (typically a low-renin population) compared to Caucasian patients, a characteristic shared by most angiotensin II antagonists and ACE inhibitors 1
- The incidence of symptomatic orthostatic hypotension after the first dose is very low (0.04%) in controlled trials 1
- Telmisartan does not cause changes in heart rate 1
- Combination with hydrochlorothiazide produces additional dose-related blood pressure reduction when patients remain hypertensive on monotherapy 1