Classification
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Arteriolar vasodilators: They directly dilate arteries e.g. nifedipine, Hydralazine, minoxidil, diazoxide. .
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Venodilators: They dilate veins. e.g. nitrates & nitrites
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Mixed vasodilators: sodium nitroprusside, Prazosin, ACEIs, trimetaphan.
General considerations:
- They usually cause reflex sympathetic stimulation (e.g. reflex tachycardia and ↑ plasma renin) so they can be combined with beta-blockers.
- They usually cause salt and water retention so they should be combined with diuretics.
- They preserve renal and cerebral blood flow.