In: Nursing
Phil is a 42-year-old who has a ventricular arrhythmia and was prescribed a Class 1 antiarrhythmic to treat his condition. He has been taking the medication for a couple of years now and recently started to have pain in his joints and has developed a rash that has become bothersome. He is refilling his prescription at your pharmacy and mentions to you that he has noticed these changes.
What medication is Phil most likely taking, and what is happening to Phil?
What course of action
should be taken?
Antiarrhythmic agents,also called as cardiac dysrhythmia medications are a group of pharmaceuticals that are used to suppress abnormal rhythms or heart (Cardiac arrhythmias). There are 5 main classes of antiarrhythmic drugs. Class 1:These agents interfere with the sodium channel. Class 2:These are anti sympathetic nervous system agents.Most agents in this class are beta blockers. Class 3: These agents affect potassium efflux. Class 4: These agents affects calcium channels and the AV node. Class 5: These agents works by unknown mechanisms.
Class 1 antiarrhythmic drugs again devided into three subclasses. Class 1a, Class 1b, Class1c. Class 1a:Drugs are fast channel blockers. Example :Quinidine, Ajmaline, Procainamide, Disopyramide. Their mechanism of action was sodium channel block and potassium channel blocking effect and affect QRS complex.These drugs prolong the action potential and has immediate effect on the 0 phase of depolarization. Class1b : Drugs :Lidocaine, phenytoin, mexiletine, tocainide. These are examples. These drugs shortened the action potential of myocardial cell and has weak effect on initiation of phase0 of depolarization by blocking sodium channels. Class1c drugs: Encainide, Felcainide, Propafenon, moricizine. These drugs show strongest effect on the initiation of phase 0 of depolarization.
Mostly prescribed drugs for ventricular arrhythmias are fast channel blockers class 1a drugs. Side effects of calcium channels blockers are : *Fatigue *joints pain,rashes, *Headache *Dizziness * Nausea. *Flushing . So we can suspect patient's presenting symptoms of Joints pain and rashes occur due to side effects is class 1 antiarrhythmic drugs. These are side effects of Procainamide . Best course of action for this patient is changing during.