Irbesartan Dosing for Hypertension
The recommended dose of irbesartan for adults with hypertension is 150 mg once daily initially, which can be increased to a maximum dose of 300 mg once daily as needed to control blood pressure. 1
Dosing Guidelines
Initial Dosing
- Standard initial dose: 150 mg once daily 1
- For volume or salt-depleted patients (e.g., those treated vigorously with diuretics or on hemodialysis): 75 mg once daily 1
Dose Titration
- If blood pressure control is not adequate at 150 mg, increase to 300 mg once daily 1, 2
- Allow 2-4 weeks between dose adjustments to assess full effect 3
- Dose-response studies show increasing antihypertensive effects up to 300 mg, with a plateau in effect at doses higher than 300 mg 2
Administration
- Can be taken with or without food 1
- Once-daily dosing provides 24-hour blood pressure control 4, 5
- May be administered as monotherapy or in combination with other antihypertensive agents 1
Special Populations
Diabetic Nephropathy
- For patients with type 2 diabetes and nephropathy: 300 mg once daily 1, 6
- Irbesartan has proven renoprotective effects in diabetic patients with albuminuria 6, 4
Renal Impairment
- No dosage adjustment is necessary for patients with renal impairment 7
- Blood pressure lowering effect is maintained in patients with chronic renal insufficiency 7
- Monitor renal function and potassium levels in patients with renal impairment 6
Elderly Patients
- Start with lower doses in elderly patients who may be at risk for orthostatic hypotension 3
- Standard dosing can be used if well tolerated 4
Combination Therapy
- For patients with stage 2 hypertension (≥140/90 mmHg), combination therapy with irbesartan and a thiazide diuretic is recommended 6
- Fixed-dose combination of irbesartan 300 mg/hydrochlorothiazide 25 mg has shown significant 24-hour blood pressure reduction 5
- Do not combine irbesartan with ACE inhibitors or direct renin inhibitors due to increased risk of hyperkalemia and renal dysfunction 6
Monitoring
- Monitor blood pressure regularly to assess response
- For patients on irbesartan, check serum creatinine/eGFR and potassium levels at least annually 3
- More frequent monitoring is recommended when initiating therapy or adjusting doses, particularly in patients with renal impairment 3
Clinical Pearls
- Irbesartan has a favorable side effect profile similar to placebo, contributing to good medication adherence 4, 8
- The trough-to-peak ratio is high (0.84-0.92), indicating consistent 24-hour blood pressure control 5
- Irbesartan provides clinically significant blood pressure lowering with a clear relationship between dose and antihypertensive effect 2
- Irbesartan 150 mg provides placebo-subtracted reductions in trough seated systolic and diastolic blood pressure of approximately 8 and 5 mmHg, respectively 2