Medications Flashcards
Calcium Channel Blockers
(Calcium channel antagonists) inhibit transport of Ca
- dilation of vasculature
- decrease in bp
- increase of blood and oxygen delivery to hear
- treats high bp
- angina
- some arrhythmias
class: dihydropyridines, non-dihydropryidines
dihydropyridines
(Ca channel blocker)
-decrease bp
-dilation of vasculature
nifedipine
Non-dihydropyridines
(Ca channel blocker)
- decrease bp
- dilation of vasculature
nitrates
-used to decrease heart’s oxygen demands
- relaxes coronary arteries, reducing workload of hear
relax muscles in blood vessels, vasodilation, decrease heart’s oxygen demands, decrease bp,
-isosobide mononitrate
-isosorbide dinitrate
-nitroglycerin
use: acute chest pain attacks, angina, prevent stress induced attacks of chest pain
Cardiac Glycosides
-naturally occurring chemicals bind to Na K ATP pump, increases intracellular Ca -increases force of contraction - slows HR -doesnt effect BP -digoxin: in addition decreases conduction through AV node, prolonging refraction, reduces arrhythmias -digitoxin
Beta Blockers
inhibits action of epinephrine or adrenaline or norepinephrone
- decreases HR
-decreases BP
-decreases force of contraction
-decreases oxygen demand
-hypertension, heart failure, arrhythmias, decrease risk of heart attacks with previous
WARNING: may increase bronchospasm, do not use for pre-exisiting pulmonary disorder, COPD, or diabetes
Digoxin
(cardiac glycoside) used for congestive heart failure, arrythmias, a-fib, a-flutter, supraventricular tachycardia
-may lead to cardiac toxicity
cardiac toxicity
(from digoxin) ventricular arrhythmias, AV block
Type 1 antiarrhythmics
sodium channel blockers, slows conduction velocity of electrical impulses and prolongs refraction
Type 1a antiarrhythmics
Na channel blocker
- decreases automatic properties of some tissue, decreases generation of spontaneous impulses
- slow conduction
- prolong refractory period
use: ventricular and supraventricular arrhythmias
Quinidine, Procainamide, disopyramide
Type 1b antiarrhythmics
Na channel blockers lowest affinity for Na channels -little effect on conduction, -shortens refractory period more affective for ventricular arrhythmias than supraventricular arrhythmias -Lidocaine, Mexiletine, Tocainide
Type 1c Antiarrhythmics
Na channel blocker
greatest affinity of Na channels
does not alter refractory period as much
can slow conduction to the point of non-conduction
affective for both ventricular and supraventricular arrhythmias
-not often used of ventricular arrhythmias because of proarrhythmias
-flecainide, propafenone, moricizine
Type III Antiarrhythmics
Potassium Channel Blockers
- delay repolarization of heart muscle
- increases refractory period, prolonging QT interval
- most effective class for treating arrhythmia
- all have different mechanism of action
- amiodarone, bretylium, dofetilide, sotalol, ibutilide
ACE Inhibitors and ARB’s
- dilation of blood vessels
- lower blood pressure
- decreases fluid retention
- decreases aldosterone production
mechanism: angiotensin II increases all of the above
ACE inhibitors: inhibit angiotensin II formation
ARB’s: block action site of angiotensin II
use: hypertension
if first line diuretics don’t work
ACE inhibitors
- dilation of blood vessels
- lower blood pressure
- decreases fluid retention
- decreases aldosterone production
mechanism: angiotensin II increases all of the above
ACE inhibitors: inhibit angiotensin II formation
use: hypertension -if first line diuretics don’t work
benazepril, enalalpril, fosinpril, lisinopril, quinapril, ramipril
indicated: heart failure, previous MI, diabetes mellitus, chronic kidney disease
do not use during pregnancy due to risk of infant renal failure or death
ARB’s
- dilation of blood vessels
- lower blood pressure
- decreases fluid retention
- decreases aldosterone production
mechanism: angiotensin II increases all of the above
ARB’s: block action site of angiotensin II
use: hypertension -if first line diuretics don’t work
indication: second line therapy for heart failure, diabetes mellitus, chronic kidney disease, allergy to ACE inhibitors
do not use during pregnancy due to risk of infant renal failure or death
Diuretics
first line drugs to treat hypertension
increase urine output (diuresis)
Three main types: thiazide diuretics, loop diuretic, potassium sparing diuretics
Thiazide diuretics
hypertension medication
-preferred medication
-generally used to initiate therapy
if ineffective or patient has bp greater than 140 or 90, may be combined with another hypertensive medication
Loop diuretics
more potent diuretic
use if patient has inadequate renal function
potassium-sparing diuretics
not potent when used alone, effective when combined with thiazide or loop diuretics
aldosterone antagonist: subclass that could take up to 6 weeks to see benefits
Central alpha-agonists
block alpha-2 receptors which are responsible for increasing HR and narrowing vessels
- decrease in BP
- decrease in HR
For patients who have failed first line bp lowering medication
- use: panic disorders, hot flashes, drug withdrawal, migraine prevention
- may cause water retention, add diuretic
- clonidine, guanfacine, guanbenzene, methyldopa
Type II Antiarrythmics
-beta blockers decrease conduction velocity prolong refractory period decrease automaticity in AV node slow sinus rhythm - decrease workload -decrease oxygen demand -used to treat atrial tachycardia and atrial fibrillation -treat hypertension, bp, relieve angina
Type IV antiarrhythmics
calcium channel blockers
-slows conduction
-prolongs refractory period
treats high bp, heart failure, coronary artery disease
-can be used to treat arrhythmias originating in SA or AV node
Alpha blockers
antagonists at alpha-1 receptor in smooth muscle cell, inhibits norepinephrine, relaxation of veins and arterioles, do not act on alpha 2 therefore no increase in HR
Atropine
blocks affects of vagus nerve: vagus nerve normally decreases HR,
- blocks decrease of HR
- accelerates conduction through heart
- normally administered after epinephrine
- administered if asystole to try to return HR
