Treatment of hypertension Flashcards
diuretics ?
substance that promotes diuresis, the increased production of urine. All diuretics indirectly prevent the re-absorption of water in the kidneys!, most of them by preventing the reabsorption of sodium.
sympatolytics ?
opposes the downstream effects of post-ganglionic nerve firing in effector organs innervated by the sympathetic nervous system (SNS). They are indicated for various functions; for example, they may be used as anti-hypertensives.
what do they act on and what are they normally in terms of mechanism ?
renin angiotensin aldosterone system/axis ( RAAS). They are normally calcium channel blockers and are direct acting vasodilators.
loop diuretics ?
furosemide supplemented with spironolactone or amiloride act on proximal convuluted tubule.
thiazides ?
Bendroflumethiazide , act on distal convoluted tubule
potassium sparing ?
Not acting directly on sodium channels act on collecting ducts.
what is a side effect of diuretics ?
that because they affect the Na being reabsorbed this has a knock on effect on the K+ levels which can be dangerous
role of fermoside ?
loop diuretic and it acts by inhibiting the Na/K/2Cl – co transporter. This is not normally used as a long term drug as it has dangerous side affects that disrupt the K levels.
role of thiazide diuretics ?`
which are the most commonly used diuretic, inhibit the sodium-chloride transporter in the distal tubule. Because this transporter normally only reabsorbs about 5% of filtered sodium, these diuretics are less efficacious than loop diuretics in producing diuresis and natriuresis.
role of potassium sparing ?
diuretics inhibit the distal tubule Na+ channel and they are an aldosterone receptor antagonist.
what is aliskiren ?
renin inhibition , not prescribed in Scotland. prevents the release of Renin from the juxtaglomerular cells. This therefore results in Ang I not being converted to Ang II by the ACE. Therefore there is not a vasoconstriction of the systemic arterioles and blood pressure is decreased as a result.
ACE inhibitors ?
The angiotensin converting enzyme inhibitors work mainly in the lungs and some examples include captopril , enalapril , they all end in – pril. They inhibit the action of ACE and prevent the conversion of Ang I to Ang II and there is no constriction of the arterial blood vessels.It reduces peripheral vascular resistance (afterload), which lowers blood pressure. Dilates the efferent glomerular arteriole, which reduces intra-glomerular pressure .This reduces the aldosterone level which promotes sodium and water excretion. This can help to reduce venous return (preload), which has a beneficial effect in heart failure.
are ACE inhibitors vasodilators ?
nope
ARB”S ?
Examples include lostaran , valsartan , end in sartan.
ARBs have similar effects to ACE inhibitors, but instead of inhibiting the conversion of angiotensin I to angiotensin II, ARBs block the action of angiotensin II on the AT1 receptor.
aldosterone antagonists ?
Spironolactone and Eplerenone. They are potassium-sparing diuretics that competitively bind to the aldosterone receptor. They promote Na+ and H20 excretion in the collecting tubule and duct
