An informative site of nursing information. Mechanism of Action Antidysrhythmic drugs work by correcting abnormal cardiac function. There are four classes of antidysrhytmics which each have a different mechanism of action. Class I drugs work on sodium channels, and are subdivided in a, b, and c classes.
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An informative site of nursing information. Mechanism of Action Antidysrhythmic drugs work by correcting abnormal cardiac function. There are four classes of antidysrhytmics which each have a different mechanism of action. Class I drugs work on sodium channels, and are subdivided in a, b, and c classes. Class II drugs are beta-adrenergic blockers also called beta-blockers. Class IV drugs are calcium channel blockers which inhibit the calcium channels reducing the movement of calcium ions in the cells during action potentials.
Indications They are used to treat dysrhythmias, and some classes are also used in the treatment of angina and hypertension. Contraindictions Include known drug allergies, as well as second or third-degree AV block, a bundle branch block, cardiogenic shock, sick sinus syndrome, and other major ECG changes.
Adverse Effects Common adverse effects include hypersensitivity reactions, nausea, vomiting, diarrhea, dizziness, headache and blurred vision. Some antidysrhythmics are able to cause to dysrhythmias. Toxicity Another adverse effect is drug toxicity. The main toxic effect of antidysrhythmic drugs involve the heart, circulation and CNS. Interactions Are unique to each individual drug but can include the potentiation of anticoagulent activity with warfarin coumadin.
Magnesium Sulfate Work by other or unknown mechanisms direct nodal inhibition Used in supraventricular arrhythmias, especially in heart failure with atrial fibrillation, contraindicated in ventricular arrhythmias. Or in the case of magnesium sulfate, used in torsades de pointes. Class I agents[ edit ] The class I antiarrhythmic agents interfere with the sodium channel. Class I agents are called membrane-stabilizing agents, "stabilizing" referring to the decrease of excitogenicity of the plasma membrane which is brought about by these agents. Also noteworthy is that a few class II agents like propranolol also have a membrane stabilizing effect. Class I agents are divided into three groups Ia, Ib, and Ic based upon their effect on the length of the action potential. These agents are particularly useful in the treatment of supraventricular tachycardias.
Medications for Arrhythmia
Antiarrhythmic Drugs Therapeutic Use and Rationale The ultimate goal of antiarrhythmic drug therapy is to restore normal rhythm and conduction. When it is not possible to revert to normal sinus rhythm, drugs may be used to prevent more serious and possibly lethal arrhythmias from occurring. Antiarrhythmic drugs are used to: decrease or increase conduction velocity alter the excitability of cardiac cells by changing the duration of the effective refractory period suppress abnormal automaticity All antiarrhythmic drugs directly or indirectly alter membrane ion conductances, which in turn alters the physical characteristics of cardiac action potentials. For example, some drugs are used to block fast sodium channels. These channels determine how fast the membrane depolarizes phase 0 during an action potential. Since conduction velocity is related to how fast the membrane depolarizes, sodium channel blockers reduce conduction velocity.
Search Medications for Arrhythmia When taken exactly as prescribed, medications can do wonders. They can also prevent complications and slow the progression of coronary heart disease. Some of the major types of commonly prescribed cardiovascular medications used to treat arrhythmias are summarized in this section. Never stop taking a medication and never change your dose or frequency without first consulting your doctor. These may be given intravenously in an emergency situation or orally for long-term treatment. These drugs either suppress the abnormal firing of pacemaker tissue or depress the transmission of impulses in tissues that either conduct too rapidly or participate in reentry.
A Guide to Drugs for Arrhythmia
Sometimes these medications affect your digestive system as well. Some people report stomach issues, constipation, or diarrhea. Anticoagulants An anticoagulant is a blood-thinning medication. Your doctor may prescribe an anticoagulant if your arrhythmia puts you at risk of clots or stroke caused by a clot. For some people, an abnormal heart rhythm changes how the blood flows through their system.