HTN: Other Meds

Question 1

What are the central a-agonists?

Answer 1

• Clonidine (transdermal)**

- Methyldopa

Question 2

Central a-agonist MOA

Answer 2

-Stimulate a2 in brainstem–> activate inhibitory neuron–> dec sympathetic outflow–> dec PVR, renal vasc resistance, HR, BP

Question 3

Central a-agonist Indications

Answer 3

• HTN

- Caution with anti-HTN and vasodilators

Question 4

Central a-agonist ADRs

Answer 4

• Clonidine (most w PO): dry mouth and sedation, HTN crisis with abrupt withdrawal (1-2 missed doses)–> taper over 1-2 wks**
• Methyldopa: overt sedation, inc prolactin, + Coombs test

Question 5

What are the direct vasodilators?

Answer 5

• Hydralazine

- Minoxidil

Question 6

Direct vasodilators indications

Answer 6

• Hydralazine: HTN, pre-eclampsia/eclampsia, HF in blacks (hydralazine + isosorbide dinitrate)**
• Minoxidil: HTN, alopecia

Question 7

Vasodilator MOA

Answer 7

-Relaxes arterial** SM–> dec PVR–> reflex tachy common

Question 8

Vasodilator Pearls

Answer 8

• Give w b-blocker or centrally acting agent to minimize reflex tachy and inc CO
• Give with diuretic to avoid Na and H2O retention
• Avoid in CAD

Question 9

Vasodilator drug interactions

Answer 9

-Anti-HTN and vasodilators

Question 10

Vasodilator ADRs

Answer 10

• Hydralazine: lupus-like rxn

- Minoxidil: hirsutism, severe fluid retention (add loop), reflex tachy (add b-blocker)