antihypertensive drugs Flashcards
what is the mechanism of action of beta blockers?
block the beta adrenoreceptors in the heart, bronchi, pancreas, liver and peripheral vasculature [blood vessels outside of heart]
slow the heart and depress myocardium [heart muscles]
which beta receptors are found in the heart and in the lungs?
1 heart = B1
2 lungs = B2
what are ISA beta blockers and what do they do?
intrinsic sympathomimetic activity beta blocker
they stimulate and also block adrenergic receptors
what are the 2 benefits of ISA beta blockers?
less bradycardia and less coldness of extremities
give examples of ISA beta blockers [4]
ICE PACO
Pindolol
acebutolol
celiprolol
oxprenolol
what is the benefit of water soluble beta blockers?
what organ are they excreted by?
do not enter the blood brain barrier so cause less sleep disturbance and nightmares!
kidneys
give examples of water soluble beta blockers [4]
cans
celiprolol
atenolol
nadolol
sotalol
what are cardio SELECTIVE beta blockers and where do they work?
which patients are they used on?
they have less effects on the B2 receptors in the lungs, and work more the heart B1 receptors.
it is selective but not specific so can still affect B1 heart receptors.
can be used in hypertension in asthmatics when there is no other alternative
what are the examples of the cardio selective beta blockers? [4]
be a man
bisoprolol atenolol metoprolol acebutol nebivolol
give an example of a non cardioselective beta blocker [1]
sotalol
how often a day do short acting beta blockers have to be taken?
2/3 times a day
how often a day do long acting beta blockers have to be taken?
once daily
give examples of long acting beta blockers [4]
BACoN
bisoprolol
atenolol
celiprolol
nadolol
what are the side effects of beta blockers? [8]
coldness of extremities [not with ISA] fatigue hyperglycaemia or hypoglycaemia sleep disturbances/nightmares [not with water soluble] hypotension bradycardia bronchoconstriction masks signs of hypoglycaemia
can beta blockers be given to asthmatics?
if so which types of asthmatics?
yes but only if no other alternative
must only use cardioselective
only to patients with well controlled asthma
can beta blockers be given to asthmatic patients for co-existing conditions such as HF and following MI?
give cardioselective beta blocker at lowest dose by specialist and monitor pt for S/E
can beta blockers be used in diabetic patients?
yes but with caution and cardio selective beta blockers be used.
why are beta blockers to be used with caution in diabetic patients?
can cause hypo or hyperglycaemia
can mask symptoms of hypoglycaemia
what are the uses of beta blockers? [9]
arrythmia heart failure hypertension angina myocardial infarction anxiety migraine prophylaxis thyrotoxicosis glaucoma
which beta blocker is used for anxiety?
propanolol
which beta blocker is used for arrythmia?
sotalol and esmolol
which beta blocker is used for migraine prophylaxis?
propanolol
what are the contra indications of beta blockers? [4]
worsening unstable heart failure
patients with 2nd or 3rd degree heart block [arrythmia]
pt with history of asthma, bronchospasm, obstructive airway disease
frequent episodes of hypoglycaemia
what are the cautions of beta blockers? [7]
pt with 1st degree AV heart block
diabetics
concurrent use with verapamil and diltiazem [can cause heart block]
stable heart failure
symptoms of thyrotoxicosis and hypoglycaemia
pt with severe hypotension and bradycardia
may reduce response to adrenaline
what are the 2 important interactions of beta blockers?
- iv verapamil and beta blockers increase risk of hypotension and heart failure
- concurrent use with verapamil or rate limiting CCB such as diltiazem as can increase risk of heart block
what is the mechanism of action of calcium channel blockers?
interfere with inward displacement of calcium ions
what are the 3 different classes of CCBs?
benzothiapines
dihydropines
phenylaklyamines
give some examples of the dihydropyridines CCB drug class. [5]
how do they work?
amlodIPINE, nifediPINE, lercanidipine, lacidipine and felodipine
work by relaxing smooth muscle and widening vessels. no anti-arrhythmic effects and do not work directly on heart
which 2 CCBs should be brand specific for the MR preparations?
amlodipine and nifedipine
give an example of phenylaklyamine CCB
how do they work?
verapamil
minimal vasodilatory effects but does have cardiac depressant effects [slow heart rate] so can cause heart failure
what side effect can verapamil cause?
constipation
give an example of a benzothiapine CCB?
how do they work?
diltiazem
have BOTH vasodilatory and cardiac depressant effects
which other drugs should benzothiazepines [eg diltiazem] be used with caution with and why?
beta blockers bc high risk of bradycardia
do CCB reduce risk of myocardial infarction in unstable angina?
no
when is verapamil and diltiazem used in unstable angina?
when pt are resistant to treatment with beta blockers
why is the sudden withdrawal of beta blockers bad in pt with unstable angina?
may worsen angina and lead to heart attack
what are the 2 prescribing and dispensing informations regarding diltiazem?
1: different versions of MR dilitazem containing more than 60mg may not have the same clinical effect
2. prescribers should prescribe by brand to prevent confusion
give 3 examples of other anti-anginal drugs
nicorandil
ivabradine
ranolazine
what are nicorandil, ivabradine and ranolazine used to treat?
long term treatment of angina
what are the side effects of calcium channel blockers? [7]
ankle swelling flushing headaches postural hypotension dizziness GI reactions skin reactions
what is the mechanism of action of thiazide like diuretics?
inhibit sodium reabsorption in the distal convulated tubule
what is the onset of action of thiazide diuretics and how long do the effects last for?
onset: 1-2 hours
lasts for 12-24 hours
when during the day should thiazide diuretics be given and why?
in the morning to prevent diuresis [increased urination that interferes with sleep]
what are low doses of thiazide diuretics used to treat?
what are high doses of thiazide diuretics used to treat?
low: used to lower blood pressure
high: used for oedema due to coronary heart failure
what are the 3 examples of thiazide diuretics?
BIC
bendroflumethiazide
indapamide
chlortalidone
what are the contraindications of thiazide diuretics? [4]
HYPOnatraemia
HYPOkalaemia
HYPERcalcaemia
addisons disease [bc already low sodium and high potassium levels]
what are the side effects of thiazide diuretics? [4]
postural hypotension
constipation [lose lots of water]
electrolyte imbalance
headaches
can thiazide diuretics be used to treat hypertension in pregnant women?
what is the risk of them in pregnant women?
no should not be used to treat gestational hypertension
can cause neonatal thrombocytopenia, bone marrow suppression, jaundice, electrolyte imbalance
can thiazide diuretics be used with hepatic and renal impairment?
use with caution in impairment
avoid in severe liver disease
what egfr rate should thiazides and related diuretics NOT be used in?
egfr of under 30 - avoid diuretics
what are the cautions of thiazide like diuretics?
Hypokalaemia
elderly more susceptible to side effects so lower doses
adjust according to renal failure [cautioned in renal impairment]
why is hypokalaemia bad in hepatic failure?
can lead to encephalopathy [brain damage] particularly in alcoholic cirrhosis
what 2 conditions can thiazide diuretics really worsen and how?
gout and diabetes
can cause hyperglycaemia and hyperuricaemia
what is the mechanism of action of loop diuretics?
inhibit reabsorption from the ascending loop of henle
give 2 examples of loop diuretics?
furosemide
bumetanide
in what conditions can loop diuretics be used to treat?
out of loop and thiazide diuretics, which are more potent?
pulmonary oedema
loop diuretics
are loop diuretics safe in diabetes?
no can worsen diabetes and gout
what is the onset of action of furosemide and bumetanide?
when is diuresis complete? therefore how often during the day can they be given?
onset of 1 hour
diuresis complete within 6 hours
can be given TWICE daily without interfering sleep
what are the side effects of loop diuretics? [6]
headache nausea electrolyte imbalance dizziness muscle spasm fatigue
what are the contraindications of loop diuretics? [4]
renal failure
severe hypokalaemia
severe hyponatraemia
liver cirrhosis
which 2 diuretics can stain your urine slightly blue?
furosemide and triameterene [potassium sparing]
how can high doses of loop diuretics or rapid IV administration damage pt with renal impairment?
bc can cause tinnitus and deafness
give examples of potassoum sparing diuretics?
give examples of aldosterone antagonist
amiloride and triamterene
spironolactone and eplerenone
what can both potassium sparing diuretics and ace inhibitors cause a risk of?
severe hyperkalaemia
which supplements must NOT be given with potassium sparing diuretics?
potassium supplements
what are the side effects of spironolactone? [3]
electrolyte imbalance
gynaecomastia
hyperkalaemia
what is combination diuretic therapy?
strong diuretic [eg furosemide] used together with weak diuretic [eg amiloride] for pt with resistant oedema
what type of diuretic is mannitol? what is it used to treat?
osmotic diuretic
to treat cerebral oedema and raised intraocular pressure
why are mercurial diuretics hardly used?
high risk of nephrotoxicity
what is the diuretic acetazolamide used to treat?
mountain sickness prophylaxis
what are the eye drops dorzolamide and brinzolamide [diuretics] used to treat?
glaucoma
what is the mechanism of action of angiotensin converting enzyme inhibitors? [ACE]
convert angiotensin 1 to angiotensin 2
what are some indications of ACE inhibitors? [4]
heart failure
hypertension
diabetic nephropathy
prophylaxis of CV events
what are the 2 contraindications of ACE inhibitors?
- concurrent use of ace and aliskiren in pt with diabetes or with egfr under 60
- discontinue if any jaundice/ signs of hepatic impairment occur
what are the cautions of ace inhibitors?
afro-carribean pt bc risk of oedema
concomitant use with diuretics bc can drop BP
renal impairment [low dose first]
can ace inhibitors be given in pregnancy and why?
no avoid can cause skull defects, neonatal BP and renal function
why should ace inhibitors be avoided during dialysis?
can cause anaphylactoid reactions
what is the pt and carer advice for ace inhibitors?
take dose sitting down to prevent hypotension as first dose hypotension can occur
what is the monitoring requirements of ace inhibitors [2]
renal function
electrolytes
what are the directions for administration of ace inhibitors for HYPERTENSION?
take FIRST dose at night time!
which other heart meds should be discontinued before starting ACE inhibitors because of risk of hyperkalaemia?
potassium sparing diuretics or potassium supplements
in which patients should ACE inhibitors be constantly monitored in? [8]
pt with severe heart failure pt on high dose or multiple diuretics pt receiving concomitant use with aliskiren pt with hypovolaemia unstable heart failure renovascular disease hyponatraemia hypotension
what are the side effects of ace inhibitors? [7]
persistent dry cough GI problems skin reactions alopecia constipation electrolyte imbalance angiodema
can ace inhibitors be used in renal impairment?
use with caution - use low dose then titrate upwards
what can concomitant use of ace inhibitors and NSAIDs cause a risk of?
risk of renal damage
what 2 things should be checked before starting ace inhibitors?
renal function
electrolytes
give examples of ARB inhibitors?
what is the mechanism of action?
candesartan, irbesartan, losartan, valsartan
angiotensin 2 receptor antagonist
can ARB inhibitors be used in pregnancy?
avoid
what are the 2 cautions of arb inhibitors?
caution in renal impairment and in the elderly
what are the side effects of arb inhibitors? [3]
hyperkalaemia
hypotension
dizziness
give an example of a renin inhibitor
what is the mechanism of action?
aliskiren
inhibit renin [which converts angiotensin to angiotensin 1]
which drug should NOT be used in conjuction with aliskiren and why?
ace inhibitor
bc can lead to risk of hyperkalaemia, hypotension or renal impairment
