Pharmacology: Katzung Adrenoreceptor blockers Flashcards
To what class of drugs do Phentolamine and Phenoxybenzamine belong to?
They are both non-selective alpha blockers,
What is the mechanism of action for phentolamine?
competitive alpha receptor antagonism
What are the clinical uses for phentolamine?
(1) pheochromocytoma
(2) antidote to overdose of alpha agonists.
What are the adverse effects associated with phentolamine?
(1) orthostatic hypotension (due to vasodilation)
(2) reflex tachycardia
What is the mechanism of action for phenoxybenzamine?
irreversibel antagoinism of alpha receptors
What are the clinical uses for phenoxybenzamine?
(1) pheochromocytoma
(2) carcinoid (blocks serotonin receptors)
(3) mastocytosis (blocks histamine receptors)
(4) Raynaud’s phenomenon
What are the toxicities associated with phenoxybenzamine?
(1) orthostatic hypotension
(2) reflex tachycardia
(3) GI irritation
To what class of drugs do Prazosin, Doxazosin, terazosin, Tamsulosin, and Silodosin belong to?
They are selective alpha 1 blockers.
What is the mechanism of action for prazosin?
Prazosin is a competitive antagonist of alpha 1 receptors
What are the clinical uses for prazosin?
(1) hypertension
2) benign prostatic hyperplasia (prevent hesitancy
What are the adverse effects associated with prazosin?
(1) orthostatic hypertension (especially on first dose)(therefore take before bed)
(2) very little reflex tachycardia
What differentiates Doxazosin and terazosin from prazosin?
Doxazosin, and terazosin have a longer duration of action.
What differentiates Tamsulosin, and silodosin from prazosin?
Tamsulosin and silodosin are only approved for the treatment of BPH.
What class of drugs does Yohmbine belong to ?
Yohimbine is a selective alpha 2 blocker.
What are the clinical uses for Yohimbine?
Yohimbine is obsolete for the treatment of erectile dysfunction.
What are some adverse effects associated with Yohimbine?
(1) tachycardia
(2) GI upset.
To what class of drugs do Propranolol, Timolol, Betaxolol, Pindolol, and nadolol belong to?
They are all Non-selective beta blockers
What is the mechanims of action for proranolol?
Propranolol is a competitive antagonist of beta receptors.
What are the clinical uses for propranolol?
(1) Angina
(2) Arrythmias
(3) Hypertension
(4) tremor
(5) stage fright
(6) migraine
Can work as a local anesthetic
What adverse effects are associated with propranolol?
(1) bronchospasm
(2) AV block
(3) heart failure
(4) CNS sedation
(5) lethargy
(6) Sleep disturbances.
What differentiates timolol, and betaxolol from propranolol?
Timolol and betaxolol lack anesthetic action and are useful in glaucoma.
What differentiates pindolol and acebutolol from propranolol?
pindolol is a partial agonist and is possibly safer for use with asthma. (less likely to cause bronchospasm)
What differentiates Nadolol from propranolol?
Nadolol is longer acting and has less CNS effect than propranolol.
To what class of drugs do atenolol, Esmolol, metoprolol, acebutolol, and Nebivolol belong to?
They are selective beta 1 blockers
What is the mechanism of action for atenolol?
Atenolol is a competitive beta 1 blocker
What are the clinical uses for atenolol?
(1) hypertension
(2) angina
(3) arrythmias
What are the adverse effects associated with atenolol?
(1) bronchospasm (less than propranolol)
(2) AV block
(3) heart failure
(4) CNS sedation
(5) lethargy
(6) Sleep disturbances.
What is esmolol used for?
Esmolol is used for perioperative and thyroid storm arrythmias and hypertensive emergencies.
What is the metoprolol used for?
Similar to atenolol reduces mortality in heart failure.
What is unique about nebivolol?
Nebivolol is a new oral beta 1 selective blocker with additional vasodilatory action.
To what class of drugs does Butoxamine belong to?
butoxamine is a beta 2 selective blocker
What are the clinical uses and adverse affects associated with butoxamine?
butoxamine is only used for research and is known to cause bronchospasm
To what class of drugs do Labetalol and carvedilol belong to?
They are alpha and beta blockers
What is the mechanism of action for Labetalol?
Labetalol binds and blocks both alpha and beta receptors.
What are the clinical uses for Labetalol?
(1) Hypertension
2) hypertensive emergencies (IV
What are the adverse effects associated with labetalol?
Similar to atenolol
1) bronchospasm (less than propranolol)
(2) AV block
(3) heart failure
(4) CNS sedation
(5) lethargy
(6) Sleep disturbances.
What is Carvedilol used for?
Like labetalol carvedilol reduces mortality in heart failure.
What is the longest acting beta blocker?
Nadolol
