HTN: A/B Blockers

Question 1

What are the long-acting (QD) alpha blockers? Short acting?

Answer 1

• Long acting: terazosin, doxazosin**

- Short acting: prazosin

Question 2

Alpha-blocker MOA

Answer 2

• a1 selective–> decrease arterial psi by dilating resistance and capacitance vessels
• Greatest BP reduction when upright
• Fluid retention common when not pair with diuretic**

Question 3

Alpha-blocker indications

Answer 3

• BPH–> less use now with Tammy
• Expulsive therapy for ureteral stones
• HTN–> less use given poor data
• Prazosin used in combat vets with PTSD but poor data

Question 4

Alpha-blocker Pearls

Answer 4

• Less tachy but more postural hypoTN (esp in first few doses)**
• AVOID vasodilators (nitrates, PDE5) and decongestants (increase bladder neck tone and urinary retention)

Question 5

Alpha-blocker ADR

Answer 5

• Postural hypoTN/dizziness VERY common in 1st few doses** (take at bedtime)
• Drowsiness/fatigue
• Nasal congestion/rhinitis**
• Retro ejac
• Floppy iris syndrome

Question 6

What are the non-selective B-blockers?

Answer 6

• Propranolol**
• Nadolol
• Timolol
• Ass with bronchospasm

Question 7

What are the selective B-blockers?

Answer 7

• Metoprolol Tartrate (IR) & Metoprolol Succinate (ER, used in HF)**
• Atenolol
• Esmolol
• Betaxolol
• Bisoprolol
• Less likely to cause bronchospasm

-Best for post-AMI, HF, AF, etc

Question 8

B-blockers with vasodilation?

Answer 8

• Used for CHF > HTN
• Carvedilol**
• Labetalol
• Nebivolol

Question 9

B-Blocker MOA

Answer 9

-Competitive inhibitors of catecholamines at B-receptors

• B1 (heart): increase HR, contractility, AV conduction
• B2 (Bronchial/peripheral SM > heart): vasodilation and bronchodilation

Question 10

B-Blocker Cardiac Indications

Answer 10

• HTN
• Stable/unstable angina (for sx and exercise tolerance)
• Post-AMI (at least 2-3 yrs)
• Systolic HF/HFrEF (indefinitely)
• Certain arrhythmias (AF)
• Periop CV risk

Question 11

B-Blocker non-cardiac Indications**

Answer 11

• Propranolol for proliferating infantile hemangioma
• Migraine
• Essential tremor
• Sx mgmt of pheochromocytoma/hyperthyroid

Question 12

B-Blocker Pearls

Answer 12

• Monotherapy less sensitive in blacks**
• Taper 1-3 wks–> accelerated angina, AMI, death if abrupt stop (pts w ischemic HD)**
• Don’t give to pts on cocaine
• Generally less effective in preventing CV events (esp CVA) compared to ACE, ARB, CCB**

Question 13

B-blockers and HF

Answer 13

• Carvedilol
• Metoprolol succinate if symptomatic hypoTN or ventricular arrhythmia
• Long term use= reduced hospitalizations, improves sx, QOL and survival
• STABLE patients with EF 40% or less

Question 14

B-Blockers Precautions/CI

Answer 14

• Asthma/COPD (non-selective)
• 2nd or 3rd degree AV block
• Sick Sinus Syndrome (unless used with pacer)
• Brady <50 bpm

Question 15

B-Blocker Drug interactions

Answer 15

• Propranolol, metoprolol, carvedilol 2D6 subs
• Careful with CCB and antiarrhythmics
• Anti-HTN and vasodilators
• Blunts effects of Epi (EpiPen)**

Question 16

B-Blocker ADRs

Answer 16

• Brady
• Hyperkalemia (non-selective agents)
• Fatigue/exercise intolerance
• ED
• Floppy iris (carvedilol and labetalol)
• Bronchospasm (non-selective agents)
• May mask/delay recovery from hypoglycemia–> edu with diabetics is vital**