Nonselective Alpha Antagonists
Which of the following are Nonselective Alpha Antagonists:
A. Terazosin
B. Indoramin
C. Phentolamine
D. Mirtazapine
E. Doxazosin
F. Phenoxybenzamine
G. Tamsulosin
H. Prazosin
I. Yohimbine
C. Phentolamine
F. Phenoxybenzamine
P = Poly
Phentolamine IV Dose = (2)
1. ________ ug/kg
2. ________ mg
30-70 ug/kg
1 to 5 mg
Phentolamine does NOT cause which of the following Side Effect?
A. Tachyarrhythmias
B. N/V
C. Abd Pain
D. Rebound Hypertension
D. Rebound Hypertension
this is a side effect of Clonidine
Which is True?
A. Phenoxybenzamine Alpha blockade onsetn = SLOW, up to 60 minutes
B. Phenoxybenzamine HL = 48 hours
A. Phenoxybenzamine Alpha blockade onsetn = SLOW, up to 60 minutes
HL=24 hours
Which of the following are Selective Alpha 1 Antagonists:
A. Terazosin
B. Indoramin
C. Phentolamine
D. Mirtazapine
E. Doxazosin
F. Phenoxybenzamine
G. Tamsulosin
H. Prazosin (Minipres)
I. Yohimbine
A. Terazosin
B. Indoramin
E. Doxazosin
G. Tamsulosin
H. Prazosin
sin = selective
Nonselective Alpha Antagonists (Phentolamine & Phenoxybenzamine) inhibit: (Select 2)
A. A1 Presynaptically
B. A1 Postsynaptically
C. A2 Presynaptically
D. A2 Postsynaptically
B. A1 Postsynaptically
C. A2 Presynaptically
Phentolamine Infusion Range
0.1 to 2 mg/min
T/F: Phenoxybenzamine blockade at postysynaptic alpha 1 is less intense than alpha 2
FALSE: more intense
Which is NOT an noncardiac effect of Phenoxybenzamine?
A. Alterations in Glycogenolysis & Lipolysis
B. Miosis
C. Sedation
D. Nasal Stuffiness
A. Alterations in Glycogenolysis & Lipolysis
does not cause alterations
Which of the following is NOT True of Prazosin (Minipres)?
A. Selective Postsynaptic A1 Antagonist
B. Prevents the inhibitory effect of A2 NE release
C. Less likely to cause reflex tachycardia
D. Dilates both arterioles and veins
B. Prevents the inhibitory effect of A2 NE release- leaves the inhibitory effect intact because it does not affect A2
Nonselective Alpha Blockers cause more reflex tachycardia (Phentolamine & Phenoxybenzamine)
Which of the following are TRUE of Phentolamine? (2)
A. Onset = < 1 min
B. Onset = 2 mins
C. Duration = 10 to 15 minutes
D. Duration = 5 to 10 minutes
B. Onset = 2 mins
C. Duration = 10 to 15 minutes
What is the Local Infiltration dose of Phentolamine used to treat extravasation of a sympathomimetic?
_____-_____ in 10 ml NS
5-15 mg in 10 ml NS
Which is TRUE of Phenoxybenzamine? (3)
A. Reversible Binding
B. Irreversible Binding
C. Terminated by Metabolism
D. Terminated by generation of new Alpha Receptors
A. Reversible Binding
C. Terminated by Metabolism
D. Terminated by generation of new Alpha Receptors
T/F: Phenoxybenzamine prevents inhibitory action of Epi on secretion of insulin.
TRUE
Which is NOT TRUE?
A. Prazosin (Minipres) Onset = 30min
B. Prazosin (Minipres) DOA = 4-6hr
C. Prazosin (Minipres) Elimination = Renal
C. Prazosin (Minipres) Elimination = Renal
HEPATIC ELIMINATION
The vasodilation effect of Phentolamine reflects what receptor blockade?
A1
Phentolamine Metabolism
Hepatic
Phenoxybenzamine prevents the effects of:
A. Epi
B. NE
C. Dopamine
D. Dobutamine
E. Phenylephrine
F. Ephedrine
G. Isoproterenol
E. Phenylephrine
Phenoxybenzamine CV Effects:
A. Orthostatic Hypotension
B. Increase EF
C. Increase CO
D. Decrease in RBF
A. Orthostatic Hypotension
C. Increase CO
The selective A1 Antagonists, Doxazosin, Terazosin, & Tamsulosin have a longer ________ compared to Prazosin.
A. Onset
B. Peak
C. DOA
C. DOA
Phentolamine vial = ____ mg/mL
5 mg/mL
Phentolamine does NOT cause which of the following Side Effect?
A. Tachyarrhythmias
B. N/V
C. Abd Pain
D. Rebound Hypertension
D. Rebound Hypertension
this is a side effect of Clonidine
Which is NOT a clinical use of Phenoxybenzamine?
A. Preop Control of HTN w/ Pheochromocytoma
B. Raynaud Syndrome
C. Acute (intraop) HTN Emergencies w/ Pheochromocytoma
D. Improve Urinary Flow in BPH
C. Acute (intraop) HTN Emergencies w/ Pheochromocytoma
this is a use of Phentolamine
Phenoxybenzamine Oral dose
1. ______ mg Qday
2. ______ mg/kg Qday
1. 40 to 120 mg Qday
2. 0.5 to 1.0 mg/kg Qday
Prazosin (Minipres):
- Starting dose for HTN = _______
- PO dose range = _______-_______
- Starting dose for HTN = 0.5 mg
- PO dose range = 1-20 mg