Sub-Quin Oral Warnings
Prolonged use of procainamide may frequently cause the body to make certain immune molecules (antinuclear antibodies) that may make you ill. Contact your doctor immediately if you develop symptoms of this type of immune illness (e.g., skin sores/hives, muscle/joint aches, fever, chills, painful breathing). Your doctor may be monitoring you with a blood test for these antibodies, and if you have them, your doctor will decide if continued use of this medication is right for you.
Although this medication and others like it are used to treat certain kinds of abnormal heartbeats, they may rarely cause serious (sometimes fatal) irregular heartbeats. Therefore, procainamide should be used carefully in selected patients only (see Uses section). Consult your doctor or pharmacist for more information.
Procainamide can rarely cause severe changes in blood cell counts, including white cells, red cells, and blood clotting cells (platelets). Notify your doctor immediately if you develop signs of a serious infection (e.g., fever, severe chills, persistent sore throat, muscle/joint aches), signs of anemia (e.g., tiredness, pale skin, faster heartbeat), or easy bruising/bleeding.
Sub-Quin Oral Uses
This medication is used to treat a certain serious (possibly life-threatening), persistent, abnormally fast heartbeat (sustained ventricular tachycardia). Procainamide belongs to a class of drugs known as antidysrhythmics. It works by blocking the abnormal electrical activity of an abnormal heartbeat so that the normal heartbeat can occur.How to use Sub-Quin Oral
This medication may be started at a low dose in the hospital so that your doctor can determine the best dose, increase it gradually as needed, and monitor you closely for side effects.
Different kinds of procainamide taken by mouth should be taken in different ways. Each time you get a refill, make sure you have received the correct kind of procainamide. Do not change kinds of procainamide unless directed by your doctor. Doing so could increase side effects or decrease the effectiveness of the medication.
Take this medication by mouth exactly as prescribed by your doctor. You may take it with or without food, but it is important to choose one way and take it consistently, either with or without food. Depending on the kind of procainamide you are prescribed, take it 2-4 times daily as directed.
If you are taking the extended-release tablet, do not crush or chew them. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split extended-release tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing. You may see the empty extended-release tablet shell in your stool. This is harmless.
This medication works best when the amount of drug in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals. To help you remember, take it at the same times each day. It is very important to avoid running out of this medication. Therefore, always order your refills several days early.
Do not take more or less of this drug than prescribed or stop taking it (or other heart medicines) even for a short time unless directed to do so by your doctor. Skipping or changing your dose without approval from your doctor may cause your abnormal heartbeat to return.
Contact your doctor immediately and seek emergency medical attention (e.g., call -911, have someone else drive you to a hospital emergency room) if your condition persists or worsens.
Sub-Quin Oral Side Effects
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication for a longer time may develop serious side effects, but with frequent visits to your doctor, this risk can be minimized. (See Warning section.)
Tell your doctor immediately if any of these unlikely but serious side effects occur: symptoms of liver problems (e.g., persistent nausea, stomach/abdominal pain, dark urine, yellowing eyes/skin), worsening symptoms of heart failure (e.g., ankle/leg swelling, increased tiredness, increased shortness of breath when lying down).
Tell your doctor immediately if any of these rare but very serious side effects occur: seizures, mental/mood changes (e.g., depression, confusion, unusual thoughts/behavior, hallucinations), muscle pain/weakness, dry mouth/eyes.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Sub-Quin Oral Precautions
Before taking procainamide, tell your doctor or pharmacist if you are allergic to it; or to local anesthetics (e.g., procaine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: certain heart problems (second- or third-degree atrioventricular block or bundle branch block unless you have a heart pacemaker), a certain immune problem (lupus).
Before using this medication, tell your doctor or pharmacist your medical history, especially of: first-degree atrioventricular block, new or recent heart attack, worsening chest pain (angina), low blood pressure, kidney problems, liver problems, myasthenia gravis.
Procainamide may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can infrequently result in serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.
The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using procainamide, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).
Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using procainamide safely.
Contact your doctor immediately if you develop other illnesses/conditions such as prolonged diarrhea, large quantities of diarrhea, heavy sweating, vomiting, prolonged loss of appetite, or prolonged loss of desire to drink water. These conditions could cause you to have serious changes in blood minerals, leading to increased side effects.
This drug may rarely make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
Sub-Quin Oral Interactions
Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.
This drug should not be used with the following medications because very serious interactions may occur: bepridil, cisapride, disopyramide, dofetilide, droperidol, fingolimod, halofantrine, ibutilide, mizolastine, pimozide, propafenone, ranolazine, sertindole, ziprasidone.
If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting procainamide.
Many drugs besides procainamide and those listed above may affect the heart rhythm (QT prolongation), including amiodarone, quinidine, sotalol, flecainide, haloperidol, amitriptyline, levofloxacin, ciprofloxacin, macrolide antibiotics (such as clarithromycin, erythromycin), among others. Therefore, before using procainamide, report all medications you are currently using to your doctor or pharmacist.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: cimetidine, ranitidine, alcohol, trimethoprim, succinylcholine.
Certain drugs may interfere with lab blood tests for procainamide (lidocaine, meprobamate, propranolol). Tell laboratory personnel and all your doctors if you are taking these medications.
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
Sub-Quin Oral Overdose
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: sudden fast/pounding heartbeat, dizziness, fainting, confusion, nausea, vomiting.NOTES:
Do not share this medication with others.
Laboratory and/or medical tests (e.g., EKG, procainamide blood levels, blood counts, liver/kidney blood tests, blood antinuclear antibody) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.MISSED DOSE:
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.STORAGE:
Store at room temperature between 68-77 degrees F (20-25 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
MEDICAL ALERT: Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).
Information last revised March 2013. Copyright(c) 2013 First Databank, Inc.