ARBs

Question 1

Prototype and Other Drugs

Answer 1

Prototype: Losartan (Cozaar)
Other: Valsartan (Diovan)
Irbesartan (Avapro)
Candesartan (Atacand)

Question 2

Expected Pharmacological Action

Answer 2

Blocks angiotension II Receptors

• Vasodilation (arteriolar)
• Urinary excretion of Na & H2O
• Urinary retention of potassium

Question 3

Side and Adverse Effects

Answer 3

• Angioedema (occurs less than with ACE inhibitors).
• Headache, insomnia
• Severe hypotension may occur with overdose or in volume depletion.

Question 4

Intervention

Answer 4

• Treats severe angioedema with IV epinephrine.
• Discontinue use if angioedema occurs.
• Monitor and report CNS effects.
• Monitor BP before administering losartan dose.
• Manage severe hypotension by expanding volume using IV fluid therapy.

Question 5

Administration

Answer 5

• Available for oral administration only.
• Losartan is also available in combination with thiazide diuretics, hydrochlorothiazide (Hyzaar).
• Take with or without food.
• Beginning dose is decreased for patients taking diuretics or with liver failure.

Question 6

Interactions

Answer 6

• Hypertensive drugs increase risk of hypotension.

- Phenobarbital decreases serum levels of losartan.