Procainamide

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Procainamide
Procainamide.svg
Clinical data
Pronunciation /proʊˈkeɪnəmaɪd/
Trade names Pronestyl, Procan, Procanbid, others
AHFS/Drugs.com Monograph
Routes of
administration 		IV, IM, by mouth
ATC code
Legal status
Legal status
  • UK: POM (Prescription only)
Pharmacokinetic data
Bioavailability 85% (by mouth)
Protein binding 15 to 20%
Metabolism Liver (CYP2D6-mediated)
Elimination half-life ~2.5 to 4.5 hours
Excretion Kidney
Identifiers
  • 4-amino-N-(2-diethylaminoethyl) benzamide
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard 100.000.072 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C13H21N3O
Molar mass 235.331 g·mol−1
3D model (JSmol)
  • O=C(c1ccc(N)cc1)NCCN(CC)CC
  • InChI=1S/C13H21N3O/c1-3-16(4-2)10-9-15-13(17)11-5-7-12(14)8-6-11/h5-8H,3-4,9-10,14H2,1-2H3,(H,15,17) Yes check.svgY
  • Key:REQCZEXYDRLIBE-UHFFFAOYSA-N Yes check.svgY
   (verify)

Procainamide (PCA) is a medication of the antiarrhythmic class used for the treatment of cardiac arrhythmias. It is a sodium channel blocker of cardiomyocytes; thus it is classified by the Vaughan Williams classification system as class Ia. In addition to blocking the INa current, it inhibits the IKr rectifier K+ current. [1] Procainamide is also known to induce a voltage-dependent open channel block on the batrachotoxin (BTX)-activated sodium channels in cardiomyocytes. [2]

Contents

Uses

Medical

Procainamide is used for treating ventricular arrhythmias: ventricular ectopy and tachycardia and supraventricular arrhythmias: atrial fibrillation, and re-entrant and automatic supraventricular tachycardia. [3] For example, it can be used to convert new-onset atrial fibrillation, and although was initially thought to be suboptimal for this purpose, a growing body of literature is amounting in support for this exact cause. [4] [5]

It is administered by mouth, by intramuscular injection, or intravenously. [6] [7]

Others

It has also been used as a chromatography resin because it somewhat binds protein. [8] [9] [10] [11]

Side effects

There are many side effects following the induction of procainamide. These adverse effects are ventricular dysrhythmia, bradycardia, hypotension and shock. The adverse effects occur even more often if the daily doses are increased. Procainamide may also lead to drug fever and other allergic responses. There is also a chance that drug-induced lupus erythematosus occurs, which at the same time leads to arthralgia, myalgia and pleurisy. Most of these side effects may occur due to the acetylation of procainamide. [12]

Toxicity

There is a close line between the plasma concentrations of the therapeutic and toxic effect, therefore a high risk for toxicity. [12] Many symptoms resemble systemic lupus erythematosus because procainamide reactivates hydroxylamine and nitroso metabolites, which bind to histone proteins and are toxic to lymphocytes. The hydroxylamine and nitroso metabolites are also toxic to bone marrow cells and can cause agranulocytosis. These metabolites are formed due to the activation of polymorphonuclear leukocytes. These leukocytes release myeloperoxidase and hydrogen peroxide, which oxidize the primary aromatic amine of procainamide to form procainamide hydroxylamine. The release of hydrogen peroxide is also called a respiratory burst, which occurs for procainamide in monocytes but not in lymphocytes. Furthermore, the metabolites can be formed by activated neutrophils. These metabolites could then bind to their cell membranes and cause a release of autoantibodies which would react with the neutrophils. [13] Procainamide hydroxylamine has more cytotoxicity by hindering the response of lymphocytes to T-cell and B-cell mitogens. Hydroxylamine can also generate methemoglobin, a protein that could hinder further oxygen exchange. [14]

It was also detected that the antiarrhythmic drug procainamide interferes with pacemakers. A toxic level of procainamide leads to decrease in ventricular conduction velocity and increase of the ventricular refractory period. This results in a disturbance in the artificial membrane potential and leads to a supraventricular tachycardia which induces failure of the pacemaker and death. [15] Thus, it prolongs QT interval of action potential and increases the risk of torsade de pointes. [1]

Procainamide could initiate leukopenia and/or agranulocytosis, which are serious hematologic disorders, and is also known for causing gastrointestinal disturbances and aggravating pre-existing abnormalities in impulse initiation and propagation. [3]

Pharmacology

Mechanism of action

Procainamide works as an anti-arrhythmic agent and is used to treat cardiac arrhythmia. It induces rapid block of the batrachotoxin (BTX)-activated sodium channels of the heart muscle and acts as antagonist to long-gating closures. The block is voltage-dependent and can occur from both sides; either from the intracellular or the extracellular side. Blocking from the extracellular side is weaker than from the intracellular side because it occurs via the hydrophobic pathway. Procainamide is present in charged form and probably requires a direct hydrophobic access to the binding site for blocking of the channel. Furthermore, blocking of the channel shows a decreased voltage sensitivity, which may result from the loss of voltage dependence of the blocking rate. Due to its charged and hydrophilic form, procainamide has its effect from the internal side, where it causes blockage of voltage-dependent, open channels. With increasing concentration of procainamide, the frequency of long blockage becomes less without the duration of blockage being affected. The rate of fast blocking is determined by the membrane depolarization. Membrane depolarization leads to increased blocking and decreased unblocking of the channels. Procainamide slows the conduction velocity and increases the refractory period, such that the maximal rate of depolarization is reduced. [2]

Metabolism

Procainamide is metabolized via different pathways. The most common one is the acetylation of procainamide to the less-toxic N-acetylprocainamide. [16] The rate of acetylation is genetically determined. There are two phenotypes that result from the acetylation process, namely the slow and rapid acetylator. Procainamide can also be oxidized by the cytochrome P-450 to a reactive oxide metabolite. But it seems that acetylation of the nitrogen group of procainamide decrease the amount of the chemical that would be available for the oxidative route. [17] Other metabolites of procainamide include desethyl-N-acetylprocainamide, desethylprocainamide, p-aminobenzoic acid, which are excreted via the urine. N-acetyl-4-aminobenzoic acid as well as N-acetyl-3-hydroxyprocainamide, N-acetylprocainamide-N-oxide and N-acetyl-4-aminohippuric acid are also metabolites of procainamide. [17]

Chemistry

4-amino-N-2-(diethylamino)ethyl-benzamide (also known as para-amino-N-2-(diethylamino)ethyl-benzamide because the amino substituent is attached to the para-position, Arene substitution patterns of the benzene ring) is a synthetic organic compound with the chemical formula C13-H21-N3-O. [18]

Procainamide is structurally similar to procaine, but in place of an ester group, procainamide contains an amide group. This substitution is the reason why procainamide exhibits a longer half-life time than procaine. [19] [20]

Procainamide belongs to the aminobenzamides. These are aromatic carboxylic acid derivatives consisting of an amide with a benzamide moiety and a triethylamine attached to the amide nitrogen. [18] [21] [22]

In certain lines, the para-amino group might become a target site to attach further paraphernalia, e.g. ref. Ex18 in U.S. patent 7,115,750 .

History

Procainamide was approved by the US FDA on June 2, 1950, under the brand name "Pronestyl". [23] It was launched by Bristol-Myers Squibb in 1951. [24] Due to the loss of Indonesia in World War II, the source for cinchona alkaloids, a precursor of quinidine, was reduced. This led to research for a new antiarrhythmic drug. As a result, procaine was discovered, which has similar cardiac effects as quinidine. [25] In 1936 it was found by Mautz that by applying it directly on the myocardium, the ventricular threshold for electrical stimulation was elevated. [24] This mechanism is responsible for the antiarrhythmic effect. However, due to the short duration of action, caused by rapid enzymatic hydrolysis, its therapeutic applications were limited. [26] In addition, procaine also caused tremors and respiratory depression. [26] [27] All these adverse features stimulated the search for an alternative to procaine. Studies were done on various congeners and metabolites and this ultimately led to the discovery of procainamide by Mark et al. It was found that procainamide was effective for treating ventricular arrhythmias, but it had the same toxicity profile as quinidine, and it could cause systemic lupus erythematosus-like syndrome. [25] [27] These negative characteristics slowed the search for new antiarrhythmics based on the chemical structure of procainamide. In 1970 only five drugs were reported. These were the cardiac glycosides, quinidine, propranolol, lidocaine and diphenylhydantoin. In January 1996, extended release procainamide hydrochloride (Procanbid extended-release tablets) was approved by the FDA. [28]

Related Research Articles

<span class="mw-page-title-main">Cardioversion</span> Conversion of a cardiac arrhythmia to a normal rhythm using an electrical shock or medications

Cardioversion is a medical procedure by which an abnormally fast heart rate (tachycardia) or other cardiac arrhythmia is converted to a normal rhythm using electricity or drugs. Synchronized electrical cardioversion uses a therapeutic dose of electric current to the heart at a specific moment in the cardiac cycle, restoring the activity of the electrical conduction system of the heart. Pharmacologic cardioversion, also called chemical cardioversion, uses antiarrhythmia medication instead of an electrical shock.

<span class="mw-page-title-main">Antiarrhythmic agent</span> Heart rhythm medication

Antiarrhythmic agents, also known as cardiac dysrhythmia medications, are a class of drugs that are used to suppress abnormally fast rhythms (tachycardias), such as atrial fibrillation, supraventricular tachycardia and ventricular tachycardia.

<span class="mw-page-title-main">Dofetilide</span> Antiarrhythmic medication

Dofetilide is a class III antiarrhythmic agent. It is marketed under the trade name Tikosyn by Pfizer, and is available in the United States in capsules containing 125, 250, and 500 μg of dofetilide. It is not available in Europe or Australia.

<span class="mw-page-title-main">Quinidine</span> Antiarrythmic medication

Quinidine is a class IA antiarrhythmic agent used to treat heart rhythm disturbances. It is a diastereomer of antimalarial agent quinine, originally derived from the bark of the cinchona tree. The drug causes increased action potential duration, as well as a prolonged QT interval. As of 2019, its IV formulation is no longer being manufactured for use in the United States.

<span class="mw-page-title-main">Amiodarone</span> Antiarrhythmic medication used for various types of irregular heartbeats

Amiodarone is an antiarrhythmic medication used to treat and prevent a number of types of cardiac dysrhythmias. This includes ventricular tachycardia, ventricular fibrillation, and wide complex tachycardia, atrial fibrillation, and paroxysmal supraventricular tachycardia. Evidence in cardiac arrest, however, is poor. It can be given by mouth, intravenously, or intraosseously. When used by mouth, it can take a few weeks for effects to begin.

<span class="mw-page-title-main">Ventricular tachycardia</span> Abnormally fast rhythm of the hearts ventricles

Ventricular tachycardia is a cardiovascular disorder in which fast heart rate occurs in the ventricles of the heart. Although a few seconds of VT may not result in permanent problems, longer periods are dangerous; and multiple episodes over a short period of time are referred to as an electrical storm. Short periods may occur without symptoms, or present with lightheadedness, palpitations, shortness of breath, chest pain, and decreased level of consciousness. Ventricular tachycardia may lead to coma and persistent vegetative state due to lack of blood and oxygen to the brain. Ventricular tachycardia may result in ventricular fibrillation (VF) and turn into cardiac arrest. This conversion of the VT into VF is called the degeneration of the VT. It is found initially in about 7% of people in cardiac arrest.

<span class="mw-page-title-main">Flecainide</span> Antiarrhythmic medication

Flecainide is a medication used to prevent and treat abnormally fast heart rates. This includes ventricular and supraventricular tachycardias. Its use is only recommended in those with dangerous arrhythmias or when significant symptoms cannot be managed with other treatments. Its use does not decrease a person's risk of death. It is taken by mouth or injection into a vein.

<span class="mw-page-title-main">Azimilide</span> Chemical compound

Azimilide is a class ΙΙΙ antiarrhythmic drug. The agents from this heterogeneous group have an effect on the repolarization, they prolong the duration of the action potential and the refractory period. Also they slow down the spontaneous discharge frequency of automatic pacemakers by depressing the slope of diastolic depolarization. They shift the threshold towards zero or hyperpolarize the membrane potential. Although each agent has its own properties and will have thus a different function.

<span class="mw-page-title-main">Disopyramide</span> Chemical compound

Disopyramide is an antiarrhythmic medication used in the treatment of ventricular tachycardia. It is a sodium channel blocker and is classified as a Class 1a anti-arrhythmic agent. Disopyramide has a negative inotropic effect on the ventricular myocardium, significantly decreasing the contractility. Disopyramide also has general anticholinergic effects which contribute to unwanted adverse effects. Disopyramide is available in both oral and intravenous forms. In 1972, when it was one of the only alternatives to quinidine, it was praised for being more potent and somewhat less toxic. However, a 2012 review of antiarrhythmic drugs noted that disopyramide is among the most toxic agents, with a high burden of side effects and increased mortality when used to treat atrial fibrillation.

<span class="mw-page-title-main">Acecainide</span> Antiarrythmic drug

Acecainide is an antiarrhythmic drug. Chemically, it is the N-acetylated metabolite of procainamide. It is a Class III antiarrhythmic agent, whereas procainamide is a Class Ia antiarrhythmic drug. It is only partially as active as procainamide; when checking levels, both must be included in the final calculation.

<span class="mw-page-title-main">Lorcainide</span> Antiarrythmic agent

Lorcainide is a Class 1c antiarrhythmic agent that is used to help restore normal heart rhythm and conduction in patients with premature ventricular contractions, ventricular tachycardiac and Wolff–Parkinson–White syndrome. Lorcainide was developed by Janssen Pharmaceutica (Belgium) in 1968 under the commercial name Remivox and is designated by code numbers R-15889 or Ro 13-1042/001. It has a half-life of 8.9 +- 2.3 hrs which may be prolonged to 66 hrs in people with cardiac disease.

<span class="mw-page-title-main">Pilsicainide</span> Chemical compound

Pilsicainide (INN) is an antiarrhythmic agent. It is marketed in Japan as サンリズム (Sunrythm). It was developed by Suntory Holdings Limited and first released in 1991. The JAN applies to the hydrochloride salt, pilsicainide hydrochloride.

Sodium channel blockers are drugs which impair the conduction of sodium ions (Na+) through sodium channels.

<span class="mw-page-title-main">Potassium channel blocker</span> Several medications that disrupt movement of K+ ions

Potassium channel blockers are agents which interfere with conduction through potassium channels.

<span class="mw-page-title-main">Moracizine</span> Chemical compound

Moracizine or moricizine, sold under the trade name Ethmozine, is an antiarrhythmic of class IC. It was used for the prophylaxis and treatment of serious and life-threatening ventricular arrhythmias, but was withdrawn in 2007 for commercial reasons.

<span class="mw-page-title-main">Arrhythmia</span> Group of medical conditions characterized by irregular heartbeat

Arrhythmias, also known as cardiac arrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia, and a resting heart rate that is too slow – below 60 beats per minute – is called bradycardia. Some types of arrhythmias have no symptoms. Symptoms, when present, may include palpitations or feeling a pause between heartbeats. In more serious cases, there may be lightheadedness, passing out, shortness of breath, chest pain, or decreased level of consciousness. While most cases of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure. Others may result in sudden death.

<span class="mw-page-title-main">Celivarone</span> Experimental drug being tested for use in pharmacological antiarrhythmic therapy

Celivarone is an experimental drug being tested for use in pharmacological antiarrhythmic therapy. Cardiac arrhythmia is any abnormality in the electrical activity of the heart. Arrhythmias range from mild to severe, sometimes causing symptoms like palpitations, dizziness, fainting, and even death. They can manifest as slow (bradycardia) or fast (tachycardia) heart rate, and may have a regular or irregular rhythm.

<span class="mw-page-title-main">Budiodarone</span> Chemical compound

Budiodarone (ATI-2042) is an antiarrhythmic agent and chemical analog of amiodarone that is currently being studied in clinical trials. Amiodarone is considered the most effective antiarrhythmic drug available, but its adverse side effects, including hepatic, pulmonary and thyroid toxicity as well as multiple drug interactions, are discouraging its use. Budiodarone only differs in structure from amiodarone through the presence of a sec-butyl acetate side chain at position 2 of the benzofuran moiety. This side chain allows for budiodarone to have a shorter half-life in the body than amiodarone which allows it to have a faster onset of action and metabolism while still maintaining similar electrophysiological activity. The faster metabolism of budiodarone allows for fewer adverse side effects than amiodarone principally due to decreased levels of toxicity in the body.

<span class="mw-page-title-main">AZD1305</span> Chemical compound

AZD1305 is an experimental drug candidate that is under investigation for the management and reversal of cardiac arrhythmias, specifically atrial fibrillation and flutter. In vitro studies have shown that this combined-ion channel blocker inhibits rapidly the activating delayed-rectifier potassium current (IKr), L-type calcium current, and inward sodium current (INa).

<span class="mw-page-title-main">XEN-D0101</span> Chemical compound

XEN-D0101 is an experimental drug that was developed to treat atrial fibrillation. Xention, a biopharmaceutical company based in Cambridge, England, created XEN-D0101 along with other ion channel-modulating drugs. XEN-D0101 is a selective antagonist of the voltage-gated potassium channel Kv1.5. Atrial fibrillation is the main focus of Xention’s drug development, as it is the most common cardiac arrhythmia seen in patients.

References

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  4. ↑ Stiell IG, Sivilotti ML, Taljaard M, Birnie D, Vadeboncoeur A, Hohl CM, et al. (February 2020). "Electrical versus pharmacological cardioversion for emergency department patients with acute atrial fibrillation (RAFF2): a partial factorial randomised trial". Lancet. 395 (10221): 339–349. doi:10.1016/S0140-6736(19)32994-0. PMID   32007169. S2CID   210978499.
  5. ↑ Fenster PE, Comess KA, Marsh R, Katzenberg C, Hager WD (September 1983). "Conversion of atrial fibrillation to sinus rhythm by acute intravenous procainamide infusion". American Heart Journal. 106 (3): 501–504. doi:10.1016/0002-8703(83)90692-0. PMID   6881022.
  6. ↑ Koch-Weser J, Klein SW (March 1971). "Procainamide dosage schedules, plasma concentrations, and clinical effects". JAMA. 215 (9): 1454–1460. doi:10.1001/jama.1971.03180220036006. PMID   5107621.
  7. ↑ Antman EM, Sabatine MS, eds. (2013). Cardiovascular Therapeutics: A companion to Braunwald's heart disease (4th ed.). Philadelphia, PA: Elsevier/Saunders. p. 410. ISBN   978-1-4557-0101-8.
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  13. ↑ Uetrecht J, Zahid N, Rubin R (January 1988). "Metabolism of procainamide to a hydroxylamine by human neutrophils and mononuclear leukocytes". Chemical Research in Toxicology. 1 (1): 74–78. doi:10.1021/tx00001a013. PMID   2979715.
  14. ↑ Roberts SM, Adams LE, Donovan-Brand R, Budinsky R, Skoulis NP, Zimmer H, et al. (1989). "Procainamide hydroxylamine lymphocyte toxicity--I. Evidence for participation by hemoglobin". International Journal of Immunopharmacology. 11 (4): 419–427. doi:10.1016/0192-0561(89)90089-1. PMID   2476407.
  15. ↑ Gay RJ, Brown DF (November 1974). "Pacemaker failure due to procainamide toxicity". The American Journal of Cardiology. 34 (6): 728–732. doi:10.1016/0002-9149(74)90164-7. PMID   4422040.
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  23. ↑ US Food and Drug Administration. "Drugs at FDA: FDA Approved Drug Products". USA: U.S. Food and Drug Administration (FDA). Retrieved 2012-08-13.
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