Exam 2- Renin-Angiotensin-Aldosterone Drugs

Question 1

ACE Inhibitors (ACE-I)

Answer 1

Examples:
Remember "pril"
Benazepril
*Captopril*
*Enalapril*
Fosinopril
*Lisinopril*
Quinapril
Ramipril

Block conversion of Angiotensin I to Angiotensin II
Quickly promote vasodilation
Chronically promote Na and water excretion
Protect against cardiac remodeling
Contraindicated in 2nd and 3rd trimesters of pregnancy
Tend to be K sparing (via reduced aldosterone) so limit KCl based salt-substitutes
May promote angioedema
Bradykinin may promote a chronic cough

Question 2

Angiotensin II Receptor Blockers (ARB)

Answer 2

Examples:
Remember "sartan"
*Candesartan*
*Losartan*
*Valsartan*

Block angiotensin II receptors on vasculature and adrenal glands
Rapidly promote vasodilation
Chronically enhance Na and water excretion
May confer less coughing than ACE-I
Contraindicated in 2nd and 3rd trimesters of pregnancy
Tend to be K sparing (via reduced aldosterone) so limit KCl based salt-substitutes
Less likely to promote angioedema
Do not block ACE, so touted for less cough
More expensive than ACE-I

Question 3

Aldosterone Receptor Blockers

Answer 3

Examples:
Spironolactone

Competitive inhibitor of aldosterone receptors in kidney and other tissues
Promotes Na/water excretion by actions on cortical collecting duct
Spares K from being lost
Protects against cardiac edema and remodeling
Advise against KCl containing salt substitutes
Promotes gynecomastia
May be added to ACE-I or ARB to treat aldosterone-stimulated inflammation and remodeling common to escape

Question 4

Direct Renin Inhibitors

Answer 4

Example:
Aliskiren

Binds to renin to inactive it
Acts like other inhibitors of RAAS
Expensive with no evidence the drug is better than other compounds
Commercial preparation in combination with hydrochlorthiazide still have no additional benefit