Anti-Adrenergics

Question 1

A1 B2 vascular distribution

Answer 1

A1 everywhere

B2 only coronary arteries + skeletal muscle

Question 2

Selective a1 blocker

Answer 2

Prazosin

REVERSIBLE

Question 3

Block A1 selectively?

Answer 3

Decrease BP

Reflex tach

NE only can act on the heart

Question 4

Phenoxybenzamine

Answer 4

A1 selective somewhat, but also a2

IRREVERSIBLE = must synthesize new receptors to revers

Duration = 24 hr

Question 5

Phentolamine

Answer 5

Block A1 + A2 (non-selective)

Block A1 = decrease BP

Block a2 = prevent feedback inhibtion by releasing NE, more NE released on B1, more tach

Question 6

How do selective a blocker increase tach?

Answer 6

Turn off A1, BP down, Baroreceptor turns on NE release to B1 on heart to for tach

Presynapse a2 = mediates NE release on vessel AND heart (mediate tach)

Question 7

A2 role on presynaptic membrane?

Answer 7

Sense NE in terminal, turn off NE release

Question 8

How do non-selective give WORSE tach?

Answer 8

A2 pre-synaptic mediation turned off, too much vasodilation, too much tach

Question 9

HTN?

Answer 9

Prazosin (selective A1)

Question 10

Pheochormocytoma tumor?

Answer 10

• Phenoxybenzamine (a1)
• Phentolamine (a2 - some on vessels)
• Propanolol (betas)

Tumor secretes catecholamine (NE/Epi) need to mitigate all this release by stablilizing all receptors

Question 11

Benign Prostatic hypertrophy?

Answer 11

RELAX BLADDER SMOOTH MUSCLE

• Phenoxybenzamine
• Prazosin (/terazosin)

Question 12

alpha block S.E.?

Answer 12

• Postural HypoTN
• Reflex tach (both, worse w/ non-selective)
• nasal stuffiness (a receptors in nose)
• inhibition of ejaculation

Question 13

Epi reversal

Answer 13

NORMAL

• 1st Betas = drop BP
• 2nd Alphas = raise BP

W/ ALPHA BLOCKER FIRST
*BP stays low

Question 14

Block b2 receptors?

Answer 14

Never!!! (Lungs)

Question 15

Selectivity of beta blockers

Answer 15

Best can do is B1 block 100 over b2

Block 100% of B1, blocked 50% of b2

Question 16

B2 block side effect

Answer 16

Bronchospasm

Question 17

Intrinsic sympathomimetic activity - partial b blocker

Answer 17

PARTIAL beta blocker - dampening intrinisic tone

• Pindolol
• Acebutolol

Question 18

Propanolol

Answer 18

Non-selective B1+b2

Oldest

Question 19

Non-selective B blocker S.E.

Answer 19

• Cardiac - B1 block, lower HR, CO,Exercise difficult, DOWN BP
• DOWN renin release (b1)
• Decrease in sympathetic tone via CNS
• UP VLDL/ DOWN HDL
• hypoglycemia (less with b1 selective)
• bronchospasm

Question 20

Glaucoma

Answer 20

Timolol

B1 make aqueous humor (blocking lowers pressure)

Question 21

Selective B1 blockers

Answer 21

• Atenolol

* Esmolol (t1/2 8 mins) = for ER BP reduction

Question 22

Selective B1 S.E.

Answer 22

• cardiac
• less broncho
• High doses= none are selective

Question 23

Labetalol

Answer 23

=alol = Mixed alpha beta blocker

• B:a1 (4:1) = acute management of HTN crisis
• chronic HTN

Question 24

Carvedilol

Answer 24

Mixed B:a1 (10:1)

• CHF
• Anti-htn
• anti-oxidant

Question 25

B blocker uses

Answer 25

* HTN * Cardiac arrythmias * angina * migraine prophylaxis * early MI , prophylactic after * Pheochormocytoma * HF (carvediol) * performance anxiety *possible cancer progression reduction

Question 26

b blocker S.E.

Answer 26

(b1) = down CO, Heart block, bradycardia (B2) bronchoconstriction CNS lethargy

Question 27

Guanethidine

Answer 27

COMES IN BY NET transporter, Decrease NE release overall by trapping it presynaptically (MAO breaks down) *anti-HTN (historically) SE = Postural HypoTN

Question 28

Reserpine

Answer 28

Enters lipid solube, blocks VMAT (no NE recycle) = empty presynaptic *Historically anti-HTN

Question 29

A2 in brain/ A2 ags as anti-adrenergics

Answer 29

Pre/post synaptic a2 BLOCK sympathetic outflow in brain A2 everywhere presynaptic in perpiphery

Question 30

A2 ags for anti-adrenergic

Answer 30

* Clonidine = works directly at a2 | * a-methyl-dopa = must be metabolized to a-methyl-NE

Question 31

A-methyl-dopa uses

Answer 31

ALPHA 2 ANTI-ADRENERGIC * essential hypertension * Safe in pregnancy S.E. = high autoimmune response, (+) Coomb's, (autoantibodies against Rh antigen on erythrocytes)

Question 32

Clonidine Use

Answer 32

ALPHA 2 AG ANTI-ADRENERGIC * essential HTN * Reduction of withdrawal in opioid (a2 involved) * Open-angle glaucoma (apraclonididne) * ADHD S.E. = HTN crisis with withdrawal Dry mouth, sedation

Question 33

A2 AG ANTi-adrenergic S.E.

Answer 33

* Dry mouth * HTN crisis on clonidine withdrawal * A-methyl-dopa = up immune => (+) Coomb's. (Autoantibodies against Rh antigen on erythrocytes)

Question 34

Dexmedetomide

Answer 34

A2 AG ANTI-ADRENERGIC * sedation critically ill/injured patients in intensive care, now non-intubated as well * a2s = locus coeruleus (probably)