What is the dose and frequency of Irbesartan (Angiotensin II receptor antagonist)?

From the Guidelines

Irbesartan should be prescribed at an initial dose of 150 mg once daily, with a goal dose of 150-300 mg daily, as indicated in the KDOQI clinical practice guidelines 1. The dose and frequency of irbesartan can be adjusted based on individual patient needs, with a maximum dose of 300 mg daily.

• Starting dose: 150 mg once daily
• Goal dose: 150-300 mg daily
• Maximum dose: 300 mg daily The medication should be taken at the same time each day to maintain consistent blood levels, and it can be taken with or without food. It is essential to monitor blood pressure regularly, especially when starting treatment or adjusting doses, as the full therapeutic effect may take 2-4 weeks to develop. Additionally, kidney function and potassium levels should be monitored periodically during treatment, as irbesartan can affect these parameters. The KDOQI guidelines recommend using ACE inhibitors or ARBs, such as irbesartan, to slow the progression of kidney disease in patients with hypertension and diabetes 1. Higher doses of irbesartan, up to 300 mg daily, may be necessary to achieve optimal blood pressure control and reduce proteinuria in patients with diabetic nephropathy. Regular monitoring of blood pressure, kidney function, and potassium levels is crucial to ensure the safe and effective use of irbesartan.

From the FDA Drug Label

2.2 Hypertension The recommended initial dose of irbesartan tablets is 150 mg once daily. The dosage can be increased to a maximum dose of 300 mg once daily as needed to control blood pressure [see Clinical Studies (14.1)]. 2.3 Nephropathy in Type 2 Diabetic Patients The recommended dose is 300 mg once daily [see Clinical Studies (14.2)]. 2.4 Dose Adjustment in Volume- and Salt-Depleted Patients The recommended initial dose is 75 mg once daily in patients with depletion of intravascular volume or salt (e.g., patients treated vigorously with diuretics or on hemodialysis) [see Warnings and Precautions (5.2)]. The dose and frequency of irbesartan are as follows:

• Initial dose for hypertension: 150 mg once daily, which can be increased to a maximum dose of 300 mg once daily as needed to control blood pressure 2.
• Dose for nephropathy in Type 2 Diabetic Patients: 300 mg once daily 2.
• Initial dose for volume- and salt-depleted patients: 75 mg once daily 2.

From the Research

Dose and Frequency of Irbesartan

• The dose and frequency of irbesartan vary depending on the patient's condition and the specific treatment goals.
• According to the studies 3, 4, irbesartan is effective at reducing blood pressure with once-daily administration.
• The recommended dose of irbesartan for hypertension is not explicitly stated in the provided studies, but it is mentioned that irbesartan 300mg once daily was used in the IRMA 2 trial and the IDNT 4.
• In terms of diabetic nephropathy, irbesartan 300mg once daily has been shown to exert a renoprotective effect in hypertensive patients with type 2 diabetes 4, 5.
• The studies suggest that irbesartan can be used in combination with other antihypertensive agents, such as hydrochlorothiazide, to achieve additive effects on blood pressure reduction 4.
• It is also noted that irbesartan has a high bioavailability, a long duration of action, and a small potential for pharmacological interactions, making it a useful treatment option for patients with hypertension and diabetic nephropathy 6.

Key Findings

• Irbesartan is effective at reducing blood pressure with once-daily administration 3, 4.
• Irbesartan 300mg once daily has been shown to exert a renoprotective effect in hypertensive patients with type 2 diabetes 4, 5.
• The combination of irbesartan with other antihypertensive agents can achieve additive effects on blood pressure reduction 4.
• Irbesartan has a high bioavailability, a long duration of action, and a small potential for pharmacological interactions 6.

Renal Outcomes

• The Irbesartan Diabetic Nephropathy Trial (IDNT) found that achieved systolic blood pressure (SBP) most strongly predicted renal outcomes, and that SBP >149 mmHg was associated with a 2.2-fold increase in the risk for doubling serum creatinine or ESRD compared with SBP <134 mmHg 7.
• The study also found that an additional renoprotective effect of irbesartan, independent of achieved SBP, was observed down to 120 mmHg 7.
• It is recommended to aim for a SBP target between 120 and 130 mmHg, in conjunction with blockade of the renin-angiotensin system, in patients with type 2 diabetic nephropathy 7.