Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
40 Cards in this Set
- Front
- Back
|
Undesirable side effects of drugs that antagonize NE
|
1. Postural Hypotension
2. Sedation/Depression 3. Increased GI Motility 4. Sodium Retention 5. Impaired Sexual Function |
|
|
Irreversible antagonist of alpha 1 and 2
|
Phenoxybenzamine
|
|
|
Length of time for irreversible blockade to develop
|
60-70 minutes
Lasts 3-4 days |
|
|
Effects of alpha 2 blockade in phenoxybenzamine
|
1. enhanced reflex tachycardia
2. Enhanced GI tone and motility 3. Blockade of epi's ability to inhibt insulin secretion |
|
|
Method of delivery for phenyoxybenzamine
|
Irritant properties dictate parenteral (however it is lipid soluble and gets into CNS)
|
|
|
Reversible competitive alpha 1 and 2 antagonist
|
Phentolamine
|
|
|
Addition mechanisms found in Phentolamine over Phenyoxybenzamine
|
1. Vasodilation by direct action on vascular smooth muscle
2. More intense cardiac stimulation than reflex 3. Increased GI tone, motility and secretion |
|
|
Phentolamine is primarily used in the OR because?
|
Cardiac and GI stimulation are so strong, tolerable doses have incomplete alpha blockade.
|
|
|
Prototype alpha 1 anatagonist and its half life
|
Prazosin
T1/2 = 3 hours |
|
|
differences between prazosin and phenoxybenzamine or phentolamine
|
little reflex tachy
little GI stimulation sex side effects are rare CNS effects of drowsiness, dissiness, fatigue |
|
|
This drug may cause postural hypotension with the first dose only
|
prazosin
Should be administered lose dose at night the first time |
|
|
Difference between terazosin and prazosin
|
Terazosin T1/2 = 12 hours
Prazosin T1/2 = 3 hours |
|
|
Three therapeutic uses for alpha blockers
|
Essential hypertension
Urinary Retention Pheochromocytoma |
|
|
Drugs for essential hypertension
|
Prazosin and terazosin
|
|
|
Drugs for urinary retnetion
|
terazosin helps void bladder
|
|
|
Drugs for pheochromocytoma surgery
|
Pre-op Oral phenoxybenzamine
Op IV phentolamine Cause vasodilation and increase blood volume prior to surgery |
|
|
Chronic pheyochromocytoma
|
oral phenyoxybenzamine
|
|
|
non selective beta antagonists
|
Propranolol
Nadolol Timolol Pindolol Labetalol |
|
|
Cardio effects of propranolol
|
slows all aspects of heart
decreases systolic pressure reflexive increases in PR leading to low blood flow low GFR |
|
|
Propranolol effects on exercise tolerance in partient with angina and in normal patients
|
increases tolerance with angina, but decrease tolerance in normal patients
|
|
|
Metabolic effects of propranolol
|
block insulin release and metabolism on fat and muscle
|
|
|
Toxicity of propranolol
|
Extreme case of normal actions (heart failure, bronchospasm, Na and water retention, sensitization to hypoglycemia)
|
|
|
First pass clearance of propranolol
Half life % protein bound |
50%
3 to 40 hours 90% |
|
|
Nadolol
|
Propranolol with T1/2 20-24 hours
|
|
|
2 uses of Timolol
|
1. Antihypertensive
2. Reduction of aqueues humor for glaucoma |
|
|
non-selective beta antagonist with partial agonist activity. less withdrawl symptoms
|
Pindolol
|
|
|
a alpha and beta antagonist
|
Labetalol
|
|
|
Metoprolol
|
selective beta 1 antagonist
|
|
|
Effects and toxicities of metoprolol
|
Same and propranolol without bronchiol constriction (beta 2 mediated)
|
|
|
beta 1 blocker with intrinsic sympathomimetic activity. t1/2 = 3 hours
|
Acebutolol
|
|
|
beta 1 blocker with 10 min half life. used IV for critcally ill partients for rapid withdrawl if necessary.
|
Esmolol
|
|
|
beta 1 blocker for opthalmic uses
|
Betaxolol
|
|
|
used for supraventricular tachycardia
|
Esmolol
|
|
|
beta 1 blocker with no intrinsive sympathomimetic activy
half life if 5=8 hours. does not pentetrate CNS |
Atenolol
|
|
|
Does acebutolol have intrinsic sympathomimetic activity?
|
Yes
|
|
|
Two uses for betaxolol
|
opthalmic use in glaucoma
antihypertensive |
|
|
Does atenolol have intrinsice sympathomimetic activity
|
No
|
|
|
half live of Atenolol
|
5-8 hours
|
|
|
Esmolol is approved for treatment of
|
Supraventricular tachycardia
|
|
|
T 1/2 for acebutolol
|
3 hours
|
