Drug Classification
The MOA of all type 1 antiarythmatics(three subclasses)
Na Blockers
Quinidine
Procainamide
Disopyramide
These drugs Lengthen potential
What are class 1a anti-arrythmatics?
The (d)-Enantiomer of an anti-malarial drug that is an alkaloid obtained from cinchona bark.
What is quinidine?
1. The SAR of procainamide
2. The precursor that undergoes hydrolyzation
3. The metabolic fate
4. The Cause of Lupus
1. Aromatic-----Base(seperated by the same distance)
2. Procaine(Novocain) - an ester analog that is CNS toxic
3. Acetylation of aniline & amidase action on amide bond
4.Acetylation of procainamide does not occur fast enough
Chronic ventricular ectopy & tachycardia, premature ventricular contraction
Oral, long t1/2
OCH2 soft spot
Undergoes CYP450 O-dealkylation(m-OCH2CF3 group)
What is Flecainide(Tambocur)?
The number of categories of anti-arrhytmic drugs
what is four?
Verapamil
Diltiazem
What are class IV anti-arrythmatics?
Amiodarone
Dronedarone
Sotalol
Breylium
What are Class III Anti-arrythmatic drugs?
The functional group responsible for drug induced lupus
What is Nitroso-Group
Chronic Ventricular ectopy & Tachycardia
Metbolized by CYP450 oxygenases to active metabolites(oxidative demethylation) and subsequent(Ortho-hydroylation and Meta-o-Methylation by COMT)
What is Ecainide(Enkaid)?
The MOA of class II anti-arrythmic drugs
What are Beta blockers
Flecainide
Encainide
Propafenone
Moricizine
These drugs maintain action potential
What are Class IC anti-arrythmatics?
A salt form of Quinidine
Employed orally(less frequently IM)
Ventricular and supraventricular arrythmias(acute and chronic)
T1/2 - about 6 hrs
Contaminant Dihydroquinidine, more potent and more toxic
GI Side effects
What is quinidine sulfat?
Ventricular arrhytmias, particularly for emergency use
T1/2 - 1 hr
N-dealkylation & AMidase Hydrolysis
Administered IV or less frequently IM
Does not survive first pass effect
GI & CNS adverse effects
1 amine soft-spot
1 ethyl soft-spot
what is Lidocaine(Xylocaine)?
A structural outlier but to other drugs of its class that resembles B-receptor blockers
Ventricular arryhythmias
Racemic Mixture
CYP2D6 5-hydroxylation and N-deakylation
the 5-hydroxy metabolite is a potent Na channel blocker
What is Propafenone(Rythmol)?
The MOA of class III anti-arrythmic drugs
What are K blockers
Propranolol
Sotalol
B1-Blockers
Class II Anti-arrythmatics
A highly water soluble salt form of quinidine employed for IV emergencies?
What is Quinidine Gluconate(Duraquin, Quinaglut)?
Sustained ventricular Tachycardia
metbolized by CYP450 p-hydroxylation and o-methylhydroxylation
Oral or IV
Long duration of action, t1/2 12-16hrs
What is Mexiletine(Mexitil)
1. blocks Na channels(S=R)(I)
2. Blocks B-receptors S>>R(II)
3. Block Ca channels(IV)
what are propafenones MOA
The MOA of class IV anti-arrythmic drugs
What are ca blockers?
Lidocaine
Mexiletine
Phenytoin
Tocainide
These Drugs shorten Potential
What are Class IB Anti-arrythmatics?
A salt form of Quinidine that is only slightly soluble in water, less irritating to the GI tract than the sulfate form and provides more sustained blood levels.
What is quinidine Polygalacturonate(Cardioquin)?
Employed for digitalis Induce Ventricular arryhthmias
IV(Slow infusion)& oral
Primarilly Anti-epileptic;dosage ranges overlap
Structure include Hydantoin Ring
Phenytoin Sodium(Dilantin)
The structural classifiaction of B-adrenergic antagonist
aryloxypropanolamines