More Hypertensive Drugs Flashcards
What is B1 responsible for?
increasing heart rate, force and AV node conduction velocity
What does B2 cause?
Bronchodilatation
What do Bet-blockers for hypertension block?
B1
What do beta blockers do to cardiac output?
Decrease (returns to normal over time, unlike MABP)
For what should beta blockers be used but with the advice “start low, go slow?”
heart failure
What do calcium channel blockers do?
Prevent opening of L-type channels in response to depolarization and hence limit increase in calcium
Where do calcium channel blockers work?
Heart and smooth muscle
What is Verapimil relatively selective for?
Cardiac L-type channels
What kind of compound is amlodipine?
Dihydropyridine
What is Amlodipine relatively selective for?
smooth muscle L-type channels
What kind of selectivity does diltiazem have?
Intermediate
What is a side effect of calcium channel blockers?
ankle swelling
What calcium channel blocker is used to minimise unwanted effects on cardiac muscle in patients with hypertension or heart block?
Amlodipine
Do calcium channel blockers produce coronary vasodilation or vasoconstriction?
coronary vasodilation
What are calcium channel blockers useful for?
Patients with angina and hypertension, isolated systolic hypertension, variant angina
Which calcium antagonist is usually used for dysrhythmias but should be avoided in heart failure (especially in combination with a beta blocker)?
Verapamil
What do potassium channel openers work?
Block ATP to open ATP-modulated K+ channels (KATP) channels in vascular smooth muscle
What are examples of potassium channel openers?
Minoxidil, Nicorandil
What is nicorandil used in?
Angina
What is Minoxidil used in?
last resort for hypertension
What are Minoxidil’s side effects and how can these be prevented?
Reflex tachycardia (use b-blocker) and salt and water retention (use diuretic)
What do alpha blockers do?
Cause vasodilation by blocking alpha 1 adrenoceptors
What are examples of alpha blockers?
Prazosin and doxazosin
What is another use of alpha blockers other than hypertension?
Benign prostatic hyperplasia
What type of diuretic is Bendroflumethiazide?
Thiazide
How do thiazide diuretics work?
Inhibit NaCl absorption in distal tubule by blocking Na+/Cl- cotransporter
What type of diuretic is furosemide?
Loop
How do loop diuretics work?
Inhibit NaCl absorption in thick ascending loop of Henle by blocking Na+/K+/Cl- cotransporter
Why are loop diuretics used in oedema and heart failure?
reduce salt and water overload
What do both types of diuretic produce that is undesirable, and how can this be corrected?
Loss of potassium, corrected by potassium sparing diuretic
