What is the MOA for Class IA antiarrhythmics?
-Binds to open and inactivated sodium channels and prevents sodium
influx
- Decreases phase 0
- Decreases myocardial excitability and conduction velocity and
myocardial contractility
- results in slowing conduction velocity and increased refractoriness
what are the adverse effects of quinidine
arrhythmias (TdP), SA and AV blockade, asystole, GI distress,
cinchonism at high doses (blurred vision, tinnitus, HA, disorientation,
psychosis), increase digoxin levels
what are some drug interactions of quinidine
antifungals (itraconazole, voriconazole, posaconazole)
What is different about disopyramide MOA?
Same as other 1A's except also has a negative inotropic effect and
peripheral vasoconstriction
what are adverse effects of Procainamide?
•Reversible lupus-erythematosus-like syndrome
•Toxic concentrations may cause asystole
•CNS side effects (depression, hallucinations, psychosis)
•Hypotension (IV)
do the class 1A drugs require dose adjustments?
, YES - adjust for renal impairment
how do you dose Disopyramide?
weight based!
> 50kg start w 300mg
<50 kg start with 200 mg
how much of the oral dose of disopyramide is excreted unchanged by
the kidneys?
1/2
what are the adverse effects of Disopyramide?
anticholinergic effects, hypotension, CHF
What agents are in the Class IB antiarrhythmics?
Lidocaine
Mexiletine
What is the MOA of Class IB antiarrhythmics?
Rapidly associates and disassociates from sodium channels with actions
manifested when the cardiac cell is depolarized or rapidly firing
Shortens phase 3 repolarization and decreases the duration of AP
how is lidocaine administered? why?
IV only due to extensive first pass metabolism
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lydiaomutho. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £6.47. You're not tied to anything after your purchase.