Prazosin / Minipress

Question 1

Alternate Names / COst

Answer 1

Terazosin, doxazosin, tamulosin, Cost 4 - 21 - 71

Question 2

Drug Class

Answer 2

Pharma: alpha 1 adrenoceptor blocker
Therapeutic: antihypertensive, treatment of BPH, treatment of Raynaud’s syndrome, treatment for Kidney Stones

Question 3

Pharmacodynamics

Answer 3

Blocks alpha 1 receptors on arterioles and veins, thereby inhibiting NE mediated vasoconstriction and venoconstriction

Question 4

Pharmacokinetics

Answer 4

Available po or transdermal; variable oral bioavailability (~60%) onset 2 hr, duration 12-24 hr, extensively metabolized in liver

Question 5

Toxicity

Answer 5

Excessive hypotension with passing out, especially orthostatic, especially in patients on diuretics

Question 6

Interactions

Answer 6

additive effects with most other anti-hypertensives, especially diuretics

Question 7

Special Considerations

Answer 7

Start gradually and at bedtime, to avoid first time passing out; male patients with BPH

Question 8

Indications and Dose / Route

Answer 8

As monotherapy begin with 1 mg tid, advance to 20 mg per day divided tid

Question 9

Monitor

Answer 9

BP weight edema

Question 10

OSIN -> Block all alpha 1 receptors

Answer 10

Prazosin mostly at blood vessels, sphincter of bladder (BPH to pee), SM of ureter to pass a kidney stone and ureter with tamulosin to give for kidney stone