Alpha1 Antagonists

Question 1

What are three Alpha1 Antagonists?

Answer 1

Prazosin
Terazosin
Doxazosin

Question 2

MOA of Alpha1Anatagonists

Answer 2

act directly by blocking alpha 1 adrenergic receptors or indirectly by decreasing NE release within SNS terminals.

Question 3

What cardiovascular side effect does Prozasin not induce?

Answer 3

does not induce reflexive tachycardia

Question 4

Use of Prazosin

Answer 4

Prazosin (Minipress) is used for the treatment of HTN, but not BPH because of the frequent dosing and cardiovascular side effects

Question 5

MOA of Prazosin

Answer 5

Block Alpha1 receptors in vasculature, causing a decrease in both arterial and venous vasoconstriction.

Question 6

How is Prazosin mostly eliminated?

Answer 6

Prazosin - mostly eliminated through bile/feces

Question 7

Most common side effect of Prazosin
Terazosin
Doxazosin

Answer 7

Orthostatic Hypotension

Question 8

Adverse effect of Prazosin and Terazosin

Answer 8

risk for syncope and LOC

Question 9

What are some unique benefits of Doxazosin

Answer 9

Doxazosin has been found to decrease LDL levels and enhance insulin sensitivity, which will help treat diabetes and atherosclerosis in patients who often have all these compounding problems together

Question 10

What line of therapy are Prazosin
Terazosin, Doxazosin

Answer 10

considered second-line agents for the treatment of HTN in older men with concomitant BPH

Question 11

What is an off-label use of Prazosin?

Answer 11

Several studies have found prazosin to be a cost-effective off-label treatment of PTSD, especially for sleep disturbances.

Question 12

Can Prazosin, Terazosin, and Doxazosin be used in pregnancy?

Answer 12

NAHHHH

Question 13

What is a disadvantage of Prazosin regarding administration?

Answer 13

Prazosin has a shorter half-life and should be prescribed twice to three times a day to achieve targeted blood pressure.

Question 14

What class of medication should be avoided by patients taking Alpha1 Antagonists because they reduce the effects?

Answer 14

Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease the antihypertensive response when used with alpha1-adrenergic antagonists.

Question 15

What kind of surgical complication/syndrome can occur in those taking Alpha 1 Antagonists

Answer 15

intraoperative floppy iris syndrome during cataract surgery

Question 16

Terazosin and Doxazosin are used more for ____ than hypertension management. Why?

Answer 16

BPH - more selective to bladder alpha receptors

Question 17

What is a rare but serious adverse effect of Alpha1 Antagonists?

Answer 17

Alpha1 antagonists have been found in rare cases to cause priapism, which can lead to permanent impotence

Question 18

Of the three - prazosin, terazosin, and doxazosin - which can be used as a monotherapy and is less likely to cause postural hypotension and fluid retention?

Answer 18

Doxazosin

Question 19

To reduce potential adverse effects, patients taking a peripherally acting alpha1 antagonist should do all of the following EXCEPT: 1. Take the dose at bedtime
2. Sit up slowly and dangle their feet before standing
3. Monitor their blood pressure and skip a dose if the pressure is less than 120/80
4. Weigh daily and report weight gain of greater than 2 pounds in one day

Answer 19

3. Monitor their blood pressure and skip a dose if the pressure is less than 120/80

Question 20

Clonidine has several off-label uses, including:
1. Alcohol and nicotine withdrawal
2. Post-herpetic neuralgia
3. Both 1 and 2
4. Neither 1 nor 2

Answer 20

3. Both 1 and 2