Adrenergic Blockers Flashcards
Adrenergic Blockers
Bind to adrenergic receptors but inhibit or block stimulation of the SNS
Opposite effects of adrenergic drugs
Lyse sympathetic stimulation
Drug Effects of Alpha Blockers
Used to treat hypertension
Cause vasodilation
Relieves effects of benign prostatic hyperplasia
Raynaud’s disease, acrocyanosis, frostbite
Adverse Effects of Alpha Blockers
Palpitations, orthostatic hypotension, tachycardia, chest pain, dizziness, headache, fatigue, nausea, vomiting
First-dose phenomenon
Common Alpha Blockers
Phentolamine (Regitine)
Terazosin (Hytrin)
Tamsulosin (Flomax)
Doxazosin (Cardura)
Phentolamine (Regitine)
Most commonly used to treat the extravasation of vasoconstricting drugs such as norepinephrine, epinephrine, and dopamine
Establish a diagnosis of pheochromocytoma
Reduces vascular resistance and treats hypertension
Contraindications are hypersensitivity, MI, and CAD
Tamsulosin (Flomax)
Used primarily to treat benign prostatic hyperplasia
EXCLUSIVELY indicated for male patients
Contraindications are drug allergy and use of ED meds
Adverse effects are headache, abnormal ejaculation, rhinitis
Terazosin (Hytrin) and Doxazosin (Cardura)
Both used to treat benign prostatic hyperplasia and hypertension
Beta Blockers
Compete with epinephrine and norepinephrine
Can be selective or nonselective
Intrinsic Sympathomimetic Activity
Carvedilol and Labetalol have alpha-receptor-blocking activity, especially at higher doses
Cardioselective Beta Blockers
Reduce SNS stimulation of the heart, decrease HR, prolong SA node recovery, slow conduction rate though AV node, decrease contractility
Nonselective Beta Blockers
Cause same effects on heart as cardioselective
Constrict bronchioles and vasoconstrict blood vessels
Indications for Beta Blockers
Angina (decreases demand for oxygen)
Cardioprotective (inhibits stimulation from catecholamines, especially after MI)
Dysrhythmias (class II antidysrhythmic)
Migraines (lipophilicity allows entry into CNS)
Antihypertensive, heart failure, glaucoma
Adverse Effects of Beta Blockers
Agranulocytosis, AV block, bradycardia, heart failure, bronchospasm, may mask signs and symptoms of hypoglycemia
Carvedilol
Nonselective beta blocker and alpha1-blocker, calcium channel blocker
Used for heart failure, HTN, angina
Slows progression of heart failure
Atenolol
Cardioselective beta blocker
Prevents future heart attacks, treats HTN and angina