Procaine Amide - General Information
A derivative of procaine with less CNS action. [PubChem]
Pharmacology of Procaine Amide
Procaine Amide is an agent indicated for production of local or regional anesthesia and in the treatment of ventricular tachycardia occurring during cardiac manipulation, such as surgery or catheterization, or which may occur during acute myocardial infarction, digitalis toxicity, or other cardiac diseases. The mode of action of the antiarrhythmic effect of Procaine Amide appears to be similar to that of procaine and quinidine. Ventricular excitability is depressed and the stimulation threshold of the ventricle is increased during diastole. The sinoatrial node is, however, unaffected.
Procaine Amide for patients
The patient should be encouraged to disclose any past history of drug sensitivity, especially to procaine or other local anesthetic agents, or aspirin, and to report any history of kidney disease, congestive heart failure, myasthenia gravis, liver disease or lupus erythematosus.
The patient should be counseled to report any symptoms of arthralgia, myalgia, fever, chills, skin rash, easy bruising, sore throat or sore mouth, infections, dark urine or icterus, wheezing, muscular weakness, chest or abdominal pain, palpitations, nausea, vomiting, anorexia, diarrhea, hallucinations, dizziness or depression.
Procaine Amide Interactions
If other antiarrhythmic drugs are being used additive effects on the heart may occur with procainamide administration, and dosage reduction may be necessary.
Anticholinergic drugs administered concurrently with procainamide may produce additive antivagal effects on A-V nodal conduction, although this is not as well documented for procainamide as for quinidine.
Patients taking procainamide who require neuromuscular blocking agents such as succinylcholine may require less than usual doses of the latter, due to procainamide effects on reducing acetylcholine release.
Procaine Amide Contraindications
Complete heart block
Procainamide should not be administered to patients with complete heart block because of its effects in suppressing nodal or ventricular pacemakers and the hazard of asystole. It may be difficult to recognize complete heart block in patients with ventricular tachycardia; but if significant slowing of ventricular rate occurs during procainamide treatment without evidence of A-V conduction appearing procainamide should be stopped. In cases of second degree A-V block or various types of hemiblock, procainamide should be avoided or discontinued because of the possibility of increased severity of block, unless the ventricular rate is controlled by an electrical pacemaker.
In patients sensitive to procaine or other ester-type local anesthetics, cross sensitivity, to procainamide is unlikely. However, it should be borne in mind, and procainamide should not be used if it produces acute allergic dermatitis, asthma or anaphylactic symptoms.
An established diagnosis of systemic lupus erythematosus is a contraindication to procainamide therapy, since aggravation of symptoms is highly likely.
Torsades de Pointes
In the unusual ventricular arrhythmia called "les torsades de pointes" (twistings of the points) characterized by alternation of one or more ventricular premature beats in the directions of the QRS complexes on ECG in persons with prolonged Q-T and often enhanced U waves, Group 1A antiarrhythmic drugs are contraindicated. Administration of procainamide in such cases may aggravate this special type of ventricular extrasystole or tachycardia instead of suppressing it.
Additional information about Procaine Amide
Procaine Amide Indication: For the treatment of life-threatening ventricular arrhythmias.
Mechanism Of Action: Procaine Amide is sodium channel blocker. It stabilizes the neuronal membrane by inhibiting the ionic fluxes required for the initiation and conduction of impulses thereby effecting local anesthetic action.
Drug Interactions: Amiodarone Amiodarone increases serum levels and toxicity of procainamide
Cimetidine The histamine H2-receptor antagonist increases the effect of procainamide
Ranitidine The histamine H2-receptor antagonist increases the effect of procainamide
Ciprofloxacin The quinolone increases the effect of procainamide
Levofloxacin The quinolone increases the effect of procainamide
Ofloxacin The quinolone increases the effect of procainamide
Dihydroquinidine barbiturate Quinidine increases the effect of procainamide
Quinidine Quinidine increases the effect of procainamide
Quinidine barbiturate Quinidine increases the effect of procainamide
Ranolazine Possible additive effect on QT prolongation
Rivastigmine Possible antagonism of action
Donepezil Possible antagonism of action
Galantamine Possible antagonism of action
Cisapride Increased risk of cardiotoxicity and arrhythmias
Mesoridazine Increased risk of cardiotoxicity and arrhythmias
Thioridazine Increased risk of cardiotoxicity and arrhythmias
Terfenadine Increased risk of cardiotoxicity and arrhythmias
Ziprasidone Increased risk of cardiotoxicity and arrhythmias
Vardenafil Increased risk of cardiotoxicity and arrhythmias
Trimethoprim Trimethoprim increases serum levels of procainamide
Food Interactions: Not Available
Generic Name: Procainamide
Synonyms: Not Available
Drug Category: Antiarrhythmic Agents
Drug Type: Small Molecule; Approved
Absorption: 75 to 95%
Toxicity (Overdose): LD50=95 mg/kg (rat, IV); LD50=312 mg/kg (mouse, oral); LD50=103 mg/kg (mouse, IV); LD50=250 mg/kg (rabbit, IV)
Protein Binding: 15 to 20%
Half Life: ~2.5-4.5 hours
Dosage Forms of Procaine Amide: Tablet, extended release Oral
Chemical IUPAC Name: 4-amino-N-(2-diethylaminoethyl)benzamide
Chemical Formula: C13H21N3O
Procainamide on Wikipedia: https://en.wikipedia.org/wiki/Procainamide
Organisms Affected: Humans and other mammals