Patient Medication Information: uses, side effects, how to take - Mar-Flecainide
Serious warnings and precautions box
What MAR-FLECAINIDE is used for:
MAR-FLECAINIDE is used to prevent or treat certain types of irregular heartbeats (arrhythmias).
How MAR-FLECAINIDE works:
MAR-FLECAINIDE belongs to the group of medicines known as antiarrhythmics. It works on the heart tissue and will slow the nerve impulses in the heart. This helps the heart beat normally again.
The ingredients in MAR-FLECAINIDE are:
Medicinal ingredients: flecainide acetate
Non-medicinal ingredients: croscarmellose sodium, magnesium stearate, and microcrystalline cellulose.
MAR-FLECAINIDE comes in the following dosage forms:
- Tablets; 50 mg and 100 mg
Do not use MAR-FLECAINIDE if:
- you are allergic to flecainide acetate or any of the other ingredients in MAR-FLECAINIDE.
- you have second- or third-degree atrioventricular block (a type of heart rhythm disorder that causes the heart to beat slowly or skip beats) and do not have a pacemaker).
- you have bifascicular or trifascicular bundle branch block (a blockage of the hearts electrical conduction system) and do not have a pacemaker.
- you have a heart condition called cardiogenic shock (a life-threatening condition that occurs when the heart is not able to pump enough blood to the body).
MAR-FLECAINIDE is intended for use only in patients with life-threatening irregular heartbeats (arrhythmias). Most anti-arrhythmic drugs have the potential to cause dangerous arrhythmias; some have been shown to be associated with an increase of sudden death. Your healthcare professional will tell you about the risk and benefits of anti-arrhythmic therapy.
To help avoid side effects and ensure proper use, talk to your healthcare professional before you take MAR-FLECAINIDE. Talk about any health conditions or problems you may have, including if you:
- have low blood pressure (hypotension)
- have had a recent heart attack
- have a pacemaker
have heart problems including:
- heart failure
- atrioventricular block
- heart conduction problems
- sinus node dysfunction, a heart rhythm disorder
- have low levels of potassium in your blood
- have liver problems
- have kidney problems
are pregnant or plan to become pregnant
- are breast-feeding or plan to breast-feed
Other warnings you should know about:
Monitoring and Tests: Before you start treatment and during your treatment with MAR-FLECAINIDE, your healthcare professional may perform tests to monitor your:
- heart. MAR-FLECAINIDE can cause new heart rhythm problems or worsen existing ones.
- liver function
- blood, bone marrow and lymph nodes
- Your heart rate will be monitored using an electrocardiograph or ECG (sometimes called an EKG). This will help your doctor determine how long to treat you with MAR-FLECAINIDE.
- You may also need frequent blood tests to check your liver or kidney function.
Your healthcare professional will interpret your results and may adjust your dose or stop your treatment with MAR-FLECAINIDE.
Driving and Using Machines
MAR-FLECAINIDE can cause light headedness, dizziness, tremors and difficulty with coordination. Before you drive or do tasks that require special attention, wait until you know how MAR-FLECAINIDE affects you.
Tell your healthcare professional about all the medicines you take, including any drugs, vitamins, minerals, natural supplements or alternative medicines.
The following may [also] interact with MAR-FLECAINIDE:
- medicines used to treat high blood pressure and to control angina (chest pain) such as verapamil and propranolol.
- medicines known as diuretics (“water pills”), used to lower blood pressure.
- medicines known as anticoagulants, used to prevent blood clotting.
- other antiarrhythmic agents such as tocainide, quinidine, procainamide, and disopyramide.
- medicines known as cardiac glycosides, used to treat heart failure and irregular heartbeats such as digoxin.
How to take MAR-FLECAINIDE:
- Take MAR-FLECAINIDE exactly as your healthcare professional tells you. Do not increase or decrease your dose without talking to your healthcare professional.
Usual dose:
- Your healthcare professional will determine the right dose of MAR-FLECAINIDE for you.
- You may receive your first few doses in a hospital or clinic setting to quickly treat any serious side effects.
- Your heart rate will be monitored using an electrocardiograph or ECG (sometimes called an EKG). This will help your doctor determine how long to treat you with MAR-FLECAINIDE.
- You may also need frequent blood tests to check your liver or kidney function.
For paroxysmal supraventricular tachycardia (PSVT) and paroxysmal atrial fibrillation/flutter (PAF):
- 50 mg every 12 hours.
- Your healthcare professional may increase your dose every 4 days as needed.
- The maximum dose is 300 mg per day.
For sustained ventricular tachycardia (sustained VT):
- 100 mg every 12 hours.
- Your healthcare professional may increase your dose every 4 days as needed.
- The maximum dose is 400 mg per day.
Overdose:
Overdose symptoms may include:
- nausea
- low blood pressure
- slow heart rhythm
- sensation of tingling, pain or numbness in hands, fingers and toes
- heart conduction problems
Missed dose:
If you miss taking your dose, take it as soon as you remember. But if it is almost time for you to take the next dose, skip the missed dose and continue with your next scheduled dose. Do not take two doses at the same time.
Possible side effects from using MAR-FLECAINIDE:
- If you think you, or a person you are caring for, have taken too much MAR-FLECAINIDE, contact a healthcare professional, hospital emergency department, regional poison control centre or Health Canada’s toll-free number, 1-844 POISON-X (1-844-764-7669) immediately, even if there are no signs or symptoms.
These are not all the possible side effects you may have when taking MAR-FLECAINIDE. If you experience any side effects not listed here, tell your healthcare professional.
- abdominal pain
- chest pain
- constipation
- dizziness
- fast or pounding heartbeats
- feeling weak
- headache
- nausea
- nervousness
- shortness of breath
- skin rash
- tiredness
- trouble breathing
- vision problems
This medicine can cause changes in your heart rhythm, such as conditions called PR, QRS, or QT prolongation. It may cause fainting or serious side effects in some patients. Contact your healthcare professional right away if your symptoms do not improve or if they become worse.
Serious side effects and what to do about them
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
|---|---|---|---|
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
| Only if severe | In all cases | ||
| Only if severe | In all cases | ||
| Only if severe | In all cases | ||
| Only if severe | In all cases | ||
| Common | |||
| Arrhythmia (abnormal heart rhythms): rapid, slow or irregular heartbeat | √ | ||
| Heart failure (heart does not pump blood as well as it should): shortness of breath, fatigue and weakness, swelling in ankles, legs and feet, cough, fluid retention, lack of appetite, nausea, rapid or irregular heartbeat, reduced ability to exercise | √ | ||
| Heart problems (disorders affecting your heart muscle, valves or rhythm): chest pain, chest discomfort, high blood pressure, irregular heart rhythm, shortness of breath, fainting, swelling of the legs, ankles and feet, or weakness | √ | ||
| Palpitation (fast beating, fluttering or pounding heart): skipping beats, beating too fast, pounding, fluttering rapidly | √ | ||
| Rare | |||
| Anemia (decreased number of red blood cells): fatigue, loss of energy, irregular heartbeats, pale complexion, shortness of breath, weakness | √ | ||
| Angina (not enough oxygen to the heart muscle): discomfort in the shoulder, arm, back, throat, jaw or teeth; pain or pressure in the chest | √ | ||
| Ataxia (lack of muscle coordination): difficulty with fine motor tasks such as eating, writing or buttoning shirt, difficulty walking, loss of balance, or slurring speech | √ | ||
| Bradycardia (abnormally slow heartbeat) | √ | ||
| Cardiogenic shock (heart is not able unable to pump enough blood to the organs of the body): breathe fast, fast heartbeat, loss of consciousness, sweating, pale skin, cold hands or feet | √ | ||
| Convulsions: seizures, spasms, shaking, or fits | √ | ||
| Edema: unusual swelling of the arms, hands, legs, feet, ankles, face or airway passages | √ | ||
| Granulocytopenia (lower-than- normal number of granulocytes, a type of white blood cell that helps fight infections): infections, fever, chills, sore throat, mouth sores, and fatigue. | √ | ||
| Hypertension (high blood pressure): shortness of breath, fatigue, dizziness or fainting, chest pain or pressure, swelling in your ankles and legs, bluish colour to your lips and skin, racing pulse or heart palpitations | √ | ||
| Hypotension (low blood pressure): dizziness, fainting, light- headedness, blurred vision, nausea, vomiting, fatigue (may occur when you go from lying or sitting to standing up) | √ | ||
| Leukopenia (decreased white blood cells): infections, fatigue, fever, aches, pains and flu-like symptoms. | √ | ||
| Micturition disorder (overactive bladder): frequent or painful urination | √ | ||
| Nervous system problems: weakness or paralysis of limbs or face, difficulty speaking, severe headache, seeing, feeling or hearing things that are not there, loss of consciousness, confusion, disorientation, or trembling | √ | ||
| Pancytopenia (decreased red and white blood cells and platelets): low red blood cell count: paleness of the skin, fatigue, rapid heart rate, shortness of breath; low white blood cell count: fever, and symptoms of infection such as cough; low platelet count: bruising easily and heavy bleeding | √ | ||
| Pneumonitis (inflammation of lung tissues): shortness of breath, chest pain, cough, fatigue, fever, flushed skin and sweating | √ | ||
| Syncope (fainting): a temporary loss of consciousness due to a sudden drop in blood pressure | √ | ||
| Tachycardia (abnormally fast heartbeat) | √ | ||
| Thrombocytopenia (low blood platelets): bruising or bleeding for longer than usual if you hurt yourself, fatigue and weakness | √ | ||
| Unknown | |||
| Allergic reaction: difficulty swallowing or breathing, wheezing, drop in blood pressure, feeling sick to your stomach and throwing up, hives, rashes, or swelling of the face, lips, tongue or throat | √ | ||
| Kidney failure (severe kidney problems): confusion; itchiness or rashes; puffiness in your face and hands; swelling in your feet or ankles; urinating less or not at all; weight gain. | √ | ||
If you have a troublesome symptom or side effect that is not listed here or becomes bad enough to interfere with your daily activities, tell your healthcare professional.
Storage:
Store at room temperature (15°C to 30°C) and protect from light.
If you want more information about APO-FLECAINIDE:
- Talk to your healthcare professional
- Find the full product monograph that is prepared for healthcare professionals and includes the Patient Medication Information by visiting the Health Canada Drug Product Database website (https://www.canada.ca/en/health-canada/services/drugs-health-products/drug-products/drug-
Reporting side effects
You can report any suspected side effects associated with the use of health products to Health Canada by:
- Visiting the Web page on Adverse Reaction Reporting (canada.ca/drug-device- reporting) for information on how to report online, by mail or by fax; or
- Calling toll-free at 1-866-234-2345.
NOTE: Contact your healthcare professional if you need information about how to manage your side effects. The Canada Vigilance Program does not provide medical advice.
- product-database.html); the manufacturer’s website (www.marcanpharma.com), or by calling 1-855-627-2261.
Date of Authorization: 2026-09-25