15. Anti-arrhythmic drugs Flashcards
Vaughan William’s Classification
Class I = membrane stabilisers
Class II = B-blockers
Class III = K+ channel blockers
Class IV = Ca2+ channel blockers
Class V = Cardiac glycosides
Class VI =Miscellaneous agents that increase vagal tone
Atropine
action
admin
met
1/2 life
adverse effects
Action = blocks vagal inhibition of sinus +AV node
Admin = IV bolus
Met = Hepatic
1/2 life = Short
Adverse effects = Postural hypertension, pupil dilation, dry mouth
Isoproterenol
action
admin
met
1/2 life
adverse effects
Action = positive chronotropic effect
Admin = IV infusion
Met = 1st Pass
1/2 life = Short
Adverse effects = tachycardia, arrhythmias
Lidocaine
action
admin
met
1/2 life
adverse effects
Action = used for ventricular arrhythmias
Admin = IV infusion + bolus
Met = Hepatic 1st Pass
1/2 life = Short
Adverse effects = hypotension, heart block, neurotoxicity, fits
Verapamil
action
admin
met
adverse effects
Action = used for SV arrhythmias
Admin = Oral and IV
Met = 1st pass hepatic
Adverse effects = hypotension, heart failure, constipation
Digoxin
action
1/2 life
adverse effects
Action = SV arrhythmias, Chronic AF, HF
1/2 life = long
Adverse effects
1) Cardiac = Heart block , V+SV arrhythmias
2) Non-cardiac = Nausea + vomiting, Confusion, Constipation Visual disturbances
Amiodarone
action
met
1/2 life
adverse effects
Action = V+SV arrhythmias, VF
Met = Hepatic
1/2 life = long
Adverse effects: 1) Peripheral neuropathy 2)Pulmonary fibrosis 3) Pro-arrhythmia 4) Blue-grey skin 5) Hepatitis 6) Thyroid disturbances
Adenosine
action
admin
1/2 life
adverse effects
Action = SV arrhythmias
Admin = IV
1/2 life = short
Adverse effects = chest pains, flushing, bronchospasm, headache, AV block
B-blockers
reduce spontaneous diastolic drift and intrinsic rate of sinus + AV node
reduce HR, BP and cardiac work
reduce renin secretion
B1 blockers adverse effects
bradycardia
HF
B2 blockers adverse effects
worsening asthma
worsening intermittent claudication
cool peripheries
muscle aches
B-blockers are used to treat..
SV arrhythmia
Angina
Prophylaxis for VT
Hypertension
HF
CCBS - dyhydropyridine
vascular effects
CCBs- phenylalkylamine
cardiac effects
CCBs- benzothiazapene
both
