Beta-adrenergic blockers

Question 1

MOA

Block the SNS stimulation of the beta-adrenergic receptors by competing w/endogenous epi & nor-epi

Beta-1 receptors are primarily on the myocardium & beta-2 receptors are located on smooth muscle in bronchioles & blood vessels

Answer 1

Non-selective forms may potentially lead to bronchospasm

Question 2

Contraindications

• Bradycardia, severe pulm dz
• Raynaud’s dz
• Pregnancy, cardiogenic shock, heart block, uncompensated HF

Question 3

Interactions

• Inc hypotensive effect w/other antihypertensive drugs & diuretics
• Dec effect w/anticholinergic drugs & antacids

Answer 3

• Dec hypoglycemic effect w/other hypoglycemic drugs

Question 4

Adverse effects

• Bradycardia, depression, dizziness, HF, lethargy
• Thrombocytopenia, agranulocytosis, dry mouth, constipation/diarrhea

Answer 4

• Impotence, rash, alopecia, bronchospasm, ischemic colitis

Question 5

Nursing

• Apical pulse, resp status & BP prior to admin
• Hold if sbp <100 mmHg& HR <60 bpm
• Do not abruptly stop

Answer 5

• Get up slowly to prevent postural hypotension
• Avoid caffeine; report any signs of edema, SOB, or wt gain >2 lbs
• I&O’s; avoid caffeine

Question 6

Examples

• Atenolol
• Carvedilol
• Propranolol
• Metoprolol