antihypertensive drugs: vasodilators, centrally acting, alpha blockers

Question 1

name 3 vasodilators

Answer 1

hydralazine
sodium nitroprusside
minoxidil

Question 2

discuss use of hydralazine, a vasodilator, in hypertension

Answer 2

given by mouth as adjunct to other antihypertensives for treatment of resistant hypertension but rarely used
when used alone, causes tachycardia and fluid retention

Question 3

discuss use of sodium nitroprusside in hypertension

Answer 3

given IV to control severe hypertensive emergencies when parenteral treatment needed
unlicensed

Question 4

discuss use of minoxidil in hypertension

Answer 4

reserve for treatment of severe hypertension resistant to other drugs

Question 5

minoxidil is a vasodilator only reserved for treatment of severe hypertension resistant to other drugs. what are its effects

Answer 5

vasodilation accompanied by increased CO and tachycardia and pt develop fluid retention

Question 6

why must you give BB + diuretic (usually furosemide) alongside minoxidil

Answer 6

its vasodilation action is accompanied by increased CO and tachycardia and pt develop fluid retention

Question 7

why is minoxidil unsuitable for females

Answer 7

hypertrichosis (excessive hair growth)

Question 8

name 3 drugs that have alpha blocking and vasodilating properties and are used in hypertension

Answer 8

prazosin
doxazosin
terazosin

Question 9

name 3 centrally acting antihypertensive drugs

Answer 9

methyldopa
clonidine
moxonidine

Question 10

this is a centrally acting drug that used 3rd line (after labetolol, after MR nifedipine) in hypertension in pregnancy. on giving birth, it needs to be stopped within 2 days (can increase risk of depression) and the pt swtiched to another suitable drug.

Answer 10

methyldopa

Question 11

this centrally acting antihypertensive has the disadv that sudden withdrawal of treatment may cause severe rebound hypertension

Answer 11

clonidine

Question 12

this centrally acting drug is licensed for mild to moderate essential hypertension. it may have a role when thiazides, CCBs, ACEi and BB are not appropriate or have failed to control BP

Answer 12

moxonidine

Question 13

when can alpha adrenoceptor blockers be used in hypertension

Answer 13

they are used with other antihypertensive drugs in the treatment of resistant hypertension
resistant hypertension: give low dose spironolactone OD if K+ levels are less than or equal to 4.5; if they are more than 4.5 give a BB or AB

Question 14

why should prazosin, an alpha blocker with vasodilator properties, be introduced with caution

Answer 14

can reduce BP rapidly after first dose
counsel to take at night

Question 15

discuss use of vasodilators in hypertension

Answer 15

have potent hypotensive effect esp when used in combo with BB + thiazide