Beta-Adrenoeptor Antagonists (Beta-blockers) Flashcards
What are the beta-blockers used to treat?
Frontline for chronic hypertension* (delayed) and heart failure
*One acute hypertension drug
Beta receptors respond to what neurotransmitters?
NE and Epi (sympathetic NS)
What are the 3 types of beta receptors?
Beta 1
Beta 2
Beta 3
Where are beta 1 receptors found?
Cardiac muscle (1 heart and 2 lungs)
Where are beta 2 receptors found?
Bronchial smooth muscle (1 heart and 2 lungs)
What does activation of beta 1 receptors cause?
Acts on cardiac muscle -> Contraction
What does activation of beta 2 receptors cause?
Acts on lungs -> Bronchial smooth muscle dilitation
Name two instances it would be contraindicated to prescribe a non-selective beta blocker (Beta 1 and beta 2).
Asthma due to beta 2 block
Diabetes (patient becomes hyperglycemic due to compensation by blockage of beta 2)
Name the three of the non selective (beta 1 and beta 2) blockers.
Propranolol
Pindolol
Timolol (also glaucoma treatment)
Name the two selective (beta 1) blockers.
Atenolol (CI: pregnancy)
Metoprolol
Name the two mixed alpha and beta blocker.
Labetalol (some beta agonist action)
Carvedilol
What drugs can be used to treat ACUTE hypertension?
Labetalol (some beta agonist action)
Carvedilol
Both treat hypertensive crisis!
T/F. Beta-blockers should be tapered to prevent rebound hypertension.
True
What drug could be used to prevent rebound hypertension often associated with a patient stops taking a beta-blocker?
Pindolol (Partial agonist)
What is the cause of rebound hypertension with withdraw of beta-blockers?
Supersensitivity of receptors
