Antiphyertensives: vasodilators

1. work directly on vessel cuase direct vasodilation; uncommonly used for HTN

2. hydralazine

2.1. indications: PK of hydralazine-> short 1/2 life but effects last up to 12 hrs; liver metabolism and excretion

2.2. AE: reflex sympathetic CV effects; Immunologic rxns wuch as drug induced lupus, serum sickness w/ long term treatment

3. minoxidil

3.1. PK-> excreted unchanged in urine but mostly liver and metabolized by liver

3.2. used for severe, resistant cases of HTN in comb w/diuretics, beta blockers

3.3. AE: na/h2o retention; increase HR, contractility, fluid retention; hypertrichosis (bad for women works topically for balding men?)

4. MOA: direct arteriolar SM relaxation (potent); prob is major reflex symp NS activation causing increased HR, fluid retention, cardiac contractility