Explanation
Avapro (Irbesartan) is an angiotensin II receptor blocker (ARB) that selectively blocks the angiotensin II type 1 (AT
1) receptor. It is indicated for the treatment of
hypertension and may be used alone or with other antihypertensive agents.
Irbesartan is also indicated for diabetic nephropathy in patients with type 2 diabetes, hypertension, elevated serum creatinine, and proteinuria greater than 300 mg/day. It does not treat diabetes itself. Seizure disorders, cystic fibrosis, and depression are not indications for irbesartan.
The usual initial dose for hypertension is 150 mg orally once daily; the dose may be increased to 300 mg once daily. A lower initial dose of 75 mg once daily is recommended for patients with intravascular volume or salt depletion, including some patients receiving intensive diuretic therapy or hemodialysis.
Common clinically relevant adverse effects include dizziness and hypotension, particularly in volume-depleted patients.
Key Points:
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Irbesartan carries a boxed warning for fetal toxicity and should be discontinued as soon as pregnancy is detected.
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Monitor blood pressure, serum potassium, and renal function after initiation and dose increases.
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Avoid concurrent aliskiren use in patients with diabetes; dual renin-angiotensin system blockade increases the risks of hypotension, hyperkalemia, and renal impairment.
Exam Pearl: Unlike ACE inhibitors, ARBs do not inhibit bradykinin degradation and are less likely to cause cough.
