Flecainide

When should one not use Flecainide

• If you are allergic to flecainide or any of the ingredients in Flecainide.
• If you have heart failure or have had a heart attack and now have certain abnormal heart rhythms without symptoms.
• If you have long-standing atrial fibrillation and no attempt has been made to restore a normal heart rhythm.
• If you have weak heart pumping, shock due to heart problems, a very slow heartbeat, or very low blood pressure.
• If you are taking other Class I anti-arrhythmic medicines (similar heart rhythm medicines).
• If you have serious heart valve disease that affects blood flow.
• If you have problems with the heart's natural pacemaker or electrical conduction (such as sinus node disease or heart block), unless a pacemaker is available.
• If you have mild or symptom-free abnormal heart rhythms coming from the lower chambers of the heart.
• If you have significant electrolyte imbalance, such as very low or high potassium levels.
• If you have been diagnosed with Brugada syndrome.

Common side effects of this drug are:

• Diplopia
• Vision blurred
• Dyspnoea
• Fatigue

Other General Warnings

• You have fast or irregular heartbeats such as AV nodal tachycardia, Wolff-Parkinson-White syndrome, or troublesome episodes of atrial fibrillation, as treatment usually needs specialist or hospital supervision.
• You have had a heart attack in the past, as Flecainide may increase the risk of serious outcomes in some patients.
• Your heart rhythm becomes worse, faster, or more severe after starting the medicine, as Flecainide can sometimes trigger new or more serious arrhythmias.
• You have structural heart disease or impaired cardiac pump function; Flecainide should generally be avoided in these conditions.
• You develop atrial fibrillation after heart surgery, as extra caution is required.
• You suddenly feel your heart racing during treatment, as the ventricular rate may increase if the medication is not working properly.
• You have liver problems; Flecainide may accumulate in the body, and blood-level monitoring may be necessary.
• You have kidney problems, as dose adjustment and monitoring may be required.
• You are elderly; the medication may remain in your body longer, and doses may need adjustment.
• You are below 12 years of age, as flecainide is not recommended for children due to limited safety data.
• You have electrolyte problems, such as low or high potassium levels, which should be corrected before starting treatment.
• You have a very slow heartbeat or very low blood pressure, which must be corrected before Flecainide is used.
• You have a pacemaker, as flecainide can affect pacemaker function and may require close monitoring.
• You have a history of heart failure, enlarged heart, or difficulty with defibrillation.
• You notice ECG changes, fainting, or symptoms suggestive of Brugada syndrome, as treatment may need to be stopped.

How Does It Work?

Interactions with other medicines

• Taking flecainide with other antiarrhythmic medications can increase side effects or cause serious arrhythmias, so close electrocardiogram (ECG) monitoring may be needed.
• Flecainide should not be taken with other Class I anti-arrhythmic medicines, as this can seriously affect the heart rhythm.
• Using flecainide with beta-blockers may slow the heart too much or weaken heart pumping.
• Medications such as amiodarone can increase flecainide plasma concentrations, so the flecainide dose may need to be reduced and monitored closely.
• Certain calcium channel blockers (e.g., verapamil) should be used cautiously with flecainide, as they may affect cardiac function.
• Some medicines can increase flecainide levels in the blood, increasing the risk of side effects, including antidepressants (such as fluoxetine or paroxetine), antipsychotics, some antihistamines, antifungal medicines (such as terbinafine), and antiviral medicines (such as ritonavir).
• Other medicines can lower flecainide levels, including some antiseizure medications (phenytoin, carbamazepine), which may reduce its effectiveness.
• Diuretics, steroids, or laxatives may disturb potassium levels, which can increase the risk of heart rhythm problems while taking flecainide.
• Certain older antihistamines, antimalarial medicines, and some antipsychotics may increase the risk of dangerous heart rhythm disturbances and should be avoided.
• Flecainide may slightly increase digoxin levels; therefore, blood levels should be monitored if both medications are used together.
• Flecainide can generally be taken with blood thinners, but regular monitoring may still be needed.
• Activated charcoal (e.g., charcoal tablets) may reduce the extent of flecainide absorption when taken concurrently.

Interactions with food items

• Dairy products, such as milk, infant formula, and possibly yoghurt, may reduce the absorption of Flecainide, particularly in children and infants.
• Sudden changes in milk or dairy intake (for example, stopping milk abruptly) may affect Flecainide levels in the body.
• Avoid excessive caffeine or stimulant-containing foods, as they may worsen heart rhythm symptoms in some people.
• Maintain a balanced diet and stable eating habits to help maintain consistent flecainide levels.

Overdose

Missed a Dose