Flecatab - Dosage | Interactions | Effects

This article was medically reviewed by M.Pharm, Marko Tanaskovic on August 12, 2018. To read more about an author, click here.

Flecatab is a medicine available in Australia and contains an active substance called flecainide and belongs to a group of antiarrhythmic drugs. It is used to treat ventricular and atrial arrhythmias, including tachycardia. The mechanism of action is based on inhibition of impulse delivery through the heart, which helps the heart to rest.

Contraindications and precautions

Flecatab should not be used in patients with:

  • 2nd or 3rd degree atrioventricular block.
  • A genetic heart disease called Brugada syndrome.

Worsening of arrhythmias in patients who have experienced heart attack have been reported, and therefore Flecatab should be avoided in these patients.

Flecatab must be used with extra precautions in the following situations:

  • In patients with hepatic impairment - increased blood levels of Flecatab may occur, which increases the risk of side effects.
  • In patients with renal impairment - increased blood levels of Flecatab may occur, which increases the risk of side effects.
  • In patients who have a permanent pacemaker.
  • In patients with bradycardia (slow heart rate).
  • In patients with low blood pressure.
  • In patients who have low or high levels of potassium in the blood.
  • In elderly patients increased blood levels of Flecatab may occur, which increases the risk of side effects.
  • In patients taking diuretics - water pills (these drugs may affect blood potassium levels).

Flecatab can cause dizziness and blurred vision, and it is not recommended to drive vehicles or operate machinery while on therapy with this medicine.

It is not recommended for use in children under the 12 years of age.

Flecatab, Pregnancy and Breastfeeding

Flecatab passes through the placenta into the fetus, therefore its use during pregnancy is recommended only if the benefit to the mother outweighs the risk to the fetus. If your doctor decides that you should take this medication during pregnancy, then blood concentrations of Flecatab throughout your pregnancy should be carefully monitored.

Flecatab passes into breast milk, and it is recommended to avoid breastfeeding while taking Flecatab.


The usual recommended dose is 50-100 mg twice a day. It is best to take the tablets one hour before a meal (on an empty stomach). Make sure you take Flecatab tablets at the same time each day.

The maximum daily dose is 300 mg, although in certain situations (for the treatment of severe arrhythmias), the dose may be increased up to 400 mg per day.

The dose should be reduced in elderly and should not exceed 300 mg daily.

The dose should also be reduced in patients with kidney or liver impairment as well as in patients with a pacemaker.


Flecatab may interact with the following medicines:

  • Antidepressants, such as:
    • paroxetine
    • fluoxetine and others
  • Calcium channel blockers, such as: diltiazem and verapamil. Simultaneous administration increases the risk of side effects (tachycardia, bradycardia, chest pain, and coma).
  • Cobicistat - a medicine used in the treatment of HIV, usually in combination with other drugs. Cobicistat can increase the concentration of Flecatab in the blood and increase the risk of side effects.
  • Ritonavir - a medicine used in the treatment of HIV infection. Simultaneous administration increases the risk of dizziness, weakness and chest pain.
  • Diuretics, such as:
    • hydrochlorothiazide
    • furosemide
    • bumetanide
    • spironolactone
    • triamterene
    • amiloride
  • Other antiarrhythmics, such as:
    • dysopyrimid
    • amiodarone
    • procainamide
    • sotalol
  • Second generation H1-antihistamines, such as: terfenadine and astemizole.
  • Cimetidine - a medicine used to treat heartburn and ulcer.
  • Beta-blockers, such as:
    • propranolol
    • bisoprolol
    • carvedilol
    • metoprolol and others.
  • Antifungal drugs, such as terbinafine.
  • Digoxin - cardiotonic glycoside used for heart failure therapy.

Simultaneous administration with the following medicines increases the risk of serious cardiac arrhythmias which may have a fatal outcome:

  • Clozapine - a medicine used to treat psychiatric disorders.
  • Dolasetron - a medicine used to prevent nausea that is caused by chemotherapy.
  • Butyrophenones (antipsychotics), such as: haloperidol and droperidol.
  • Citalopram and escitalopram - selective serotonin uptake inhibitors used to treat depression and anxiety.
  • Cisapride - a medicine used to treat heartburn, which is accompanied by gastroesophageal reflux disease.
  • Methadone - an analgesic agent used in the treatment of the severe pain.
  • Pimozide - antipsychotic that belongs to the group of diphenylbutylpiperidines.
  • Fluoroquinolone antibiotics, such as: grepafloxacin, gatifloxacin, sparfloxacin and moxifloxacin.
  • Toremifen - a medicine used to treat metastatic carcinoma in postmenopausal women.

Tell your doctor about all the medicines you are taking.

Side effects

Flecatab may cause the following side effects:

  • Dizziness.
  • Weakness and tiredness.
  • Nausea and vomiting.
  • Diarrhea.
  • Flatulence.
  • Anemia caused by a reduction in the number of red blood cells.
  • Increased sweating.
  • Ringing in the ears.
  • Anxiety.
  • Depression.
  • Convulsions.
  • Motor tics.
  • Edema.
  • Hallucinations.
  • Tachycardia.
  • Bradycardia.
  • Hypotension.
  • Heart attack.

Tell your doctor if you are experiencing any side effects.

Information on this website are provided for educational purposes only and are not intended for medical advice, diagnosis or treatment.

If you have any concerns or questions about your health, you should always consult with a physician or other health-care professional.

We and our partners use technology such as cookies on our site to personalise content and ads, provide social media features, and analyse our traffic. Click below to consent to the use of this technology across the web. You can change your mind and change your consent choices at anytime by returning to this site.