Flecainide: Hi there. I was diagnosed with A... - AF Association

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Poochmom profile image

Hi there. I was diagnosed with A-Fib last year. After wearing a holter monitor my cardiologist put me on Flecainide. I’m already on bystolic (beta) and Eliquis blood thinner

I started taking the Flecainide 5 mg and as soon as I did I got constant arrhythmias. I never had that before. I stopped taking it and it stopped. Talked to my doc and she said to give it time. So I started it again and same thing. I took it for three daysI couldn’t stand it. Constant arrhythmia. I had to stop taking it. I have not consulted with my cardiologist yet after stopping because I can’t get hold of her. I’m going to find a new doc after I get this straightened out with the anti arrhythmic drug.

Has anyone had this reaction and if so, what did you do? Are their other ones out there that may not give me this side effect! I’m not going to take a drug that Makes my condition worse. Anyway sorry for the long post, I would just like to get some feedback with people’s experience with these anti arrhythmics.

Thank you!

53 Replies
Hidden profile image

I can only speak for myself and Flecainide has given me my life back. I was having two days of AF then one day off for months. 100 of Flecainide morning and evening and have the odd episode which is easily controlled by a further 100.

Poochmom profile image
Poochmom in reply to Hidden

Thanks Hylda. I guess it affects people differently. I so wish it worked for me. I’m hoping there is another one out there that won’t give me worse arrhythmia.

Hi Poochmom, here in the UK we know Bystolic as Nebivol and members of this forum have really praised that drug for having less side effects and giving them more energy.

I don't know if your Flecainide is rated differently to ours but generally here 50mg is the lowest dose taken and that's usually twice daily, but many more take 2 x 100mg daily. For me Flecainide Acetate has been a wonder drug and the only one that's helped reduce the intensity of my AF. However, I do know that it doesn't suit everyone.

I can understand you not wanting to take a drug that triggers your AF and think you are doing the right thing by contacting your cardiologist. Please let us know what she says.

Wishing you well.


Thanks Jean. Yes the Bystolic I take is wonderful. Much better than the metoprolol I was taking. No side effects with the bystolic in fact I am wondering if I should up my dose from 2.5 mg. I’ll talk to my cardiologist. Waiting fir a response to my holter monitor from two weeks ago.

Any substance that can clear a symptom also has the capacity to cause a symptom and Flecainide is notorious for that. Have you had an ECG? Are you able to monitor yourself - Kardia/Apple Watch etc? Who was the prescribing Doctor - GP, Cardiologist or EP?

In your position I would go and do a lot of research on Flecainide and then return to your doctor and ask for monitoring and then discuss the use of Flecainide, especially as it seems not to be helping you.

When I was started on Flecainide back in about 2010, I was monitored after taking my 1st dose in the clinic for 7 hours with numerous ECGs taken to ensure I didn’t have the reaction you describe. That used to be the recommendation, that 1st dose was supervised and monitored for adverse reactions.

Everyone reacts very differently to every medication so because it works for one person, it may not suit another.

Flecainide worked for me also but only for a year or so before AF broke through.

Poochmom profile image
Poochmom in reply to CDreamer

Thank you fir your response. Yes it was 50 mg. My cardiologist prescribed it over the phone and then when I told her about the reaction she tried to keep me taking it. I have done a lot of research as you suggest and find that it can cause the symptoms it’s suppose to suppress.

I do have an Apple Watch and monitor myself on a regular basis. Sometimes when I have an episode it comes up with AF and other times it’s say no AF just a fast heart rate (tachycardia). It’s odd. My attacks last less than two hours and sometimes less than one. I am wondering if I should ask to be referred to an EP.

PS - 5mg? I used to take 2 x 100mg daily.

BobD profile image

It used to be a condition here in UK that flecainde was always started in hospital under the care of a consultant. The reason being that it can cause atrial flutter in some patients which is a totally different arrhythmia to atrial fibrillation . It should also never be given if the patient has a history of cardiac artery disease so is often preceded by an echocardiogram or preferably an angiogram to check that the heart is in good mechanical health. General practitioners are not permitted to instigate prescription without consultant input either so it is a drug which can cause serious problems for some people. I suggest that you press your cardiologist before atempting to take it again.

Poochmom profile image
Poochmom in reply to BobD

Thank you Bob. Yes I will talk to her again. I tried to make an appointment but her assistant called me back and cancelled it because I just had a holter and she wouldn’t have the results back. She said the cardio would call me. I will discuss it with her but I won’t take the Flecainide again. What you describe is exactly what I experienced... atrial flutter. I dont have any structural issues so I don’t think she did anything wrong. It’s just that she tried to keep me taking it even when I told her about the flutters. We will see. I’m not jumping ship just yet.

CHRISAF18 profile image
CHRISAF18 in reply to BobD

Bob how would you describe flutter I am wondering if I am experiencing that and not ectopics or is that the same x

As above really.

It has worked wonders for me but we are all different. I assume you mean 50mg (not 5mg as this is a very low dose).

"I have not consulted with my cardiologist yet after stopping because I can’t get hold of her"

Keep pushing although I fully understand it's hard to do these days. Have you spoken to your cardio's secretary ? Sometimes they will ask questions on your behalf but it always seems to take a few days for an answer.

Good luck anyway.


Poochmom profile image
Poochmom in reply to Paulbounce

Yes I’m waiting to hear from cardio after a holter I did a week and a half ago. I’ll talk to her but I didn’t like the fact she tried to keep me taking it after I told her about the constant flutters. And yes it’s 50 mg not 5.

Thanks Bill. I’mNot sacking my cardio yet but want to really sit down and talk to her. She tried to keep me taking it even when I told her about the constant flutters that’s what bothered me. Thanks fir the input. It seems that it works well for a lot of people. Unfortunately I’m not one of them. 😀

cuore profile image
cuore in reply to Poochmom

Oh, what a bind you are in with your anti-arrhythmic drugs talking to two clinicians who are not experts in anti-arrhythmic drugs. These drugs are not to be taken lightly. Improperly administered, thy can do enough damage to our delicate electrical circuit. Your GP had no business telling you to "give it time." Time for what -- more damage? Your cardio , which I take to be your cardiologist, is saying the same thing. There are so many cardiologists out there who don't know what they are doing when it comes to electrical signals. To tell you to stay on a drug that is causing arrhythmia is mind-boggling. I would suggest going to an EP to get proper treatment. I have encountered enough horror cases , including myself, when a GP or a cardiologist tampers with our electrical signals.

I have taken 100 and 200mg flecanide at different times in my life and support the positive comments made here.

My question is were you also prescribed a beta blocker? Which (based on MY experience and advice that has been given to ME and remember that I AM NOT a doctor) you should take if you are on flecanide.

Poochmom profile image
Poochmom in reply to Jonathan_C

Hi Jonathan. Yes I am on 2.5 mg of bystolic which is a beta blocker. I am wondering if I not taking enough of that. I intend to talk to my cardiologist about that. I want to love the Flecainide but causing constant flutters doesn’t work for me. I only had it when I took the flec. Thanks for your positive words. It’s much appreciated.

Jonathan_C profile image
Jonathan_C in reply to Poochmom

I can't comment on your dose. What I do know is this: I have some wonky valves in my heart so I have seen a "plumbing" cardiologist since a young age. I went into a-fib in my early 40s and he tried to treat it and prescribed flecanide but did not prescribe a beta block. After a few breakthroughs into a-fib, while on flecanide, he referred me to an EP who assessed me and then referred me to another EP - both EPs were quite shocked that the first cardiologist had not prescribed beta blocker to accompany the flecanide ... THEIR reasoning to me, is that if you have a breakthrough on flec and are not on a beta there is a significant risk the flec will trigger atrial flutter.

Poochmom profile image
Poochmom in reply to Jonathan_C

Thank you Jonathan. I am on a beta blocker but wonder if it’s strong enough dose. We will see. I will speak with my cardiologist. She did emphatically tell me to make sure I take the beta blocker with the Flecainide.

Had the same happen to me with Flecainide........ took it for a few days and had to stop as I felt dreadful. Cardiologist agreed with my stopping and put me on Amiodarone. This is obviously not the ideal drug to be on but it is the only one I have responded to. Hopefully, after ablation this week, there will be a possibility at some point in the most too distant future, that I will be able to come off it.

Poochmom profile image
Poochmom in reply to Ducky2003

Thank you so much Ducky 2003. I was beginning to think I was just being a wimp due to all the positives from people. I am going to talk to cardiologist to see about another drug for the time being to see if it works.

Ducky2003 profile image
Ducky2003 in reply to Poochmom

I felt worse taking it than not so I can sympathise. Hope you can get sorted out asap.😊.

Visigoth profile image
Visigoth in reply to Ducky2003

That’s interested me because I am also on amiodarone and currently trying to decide whether to go for ablation or not. Please let us know how you get on! Do you have to stop the amiodarone prior to or post ablation? I am terrified of going back to what I experienced before, as my symptoms have been well controlled on amiodarone. I too tried flecainide years ago and it made my symptoms worse, so I was put on propafenone, but my cardio says that is no longer recommended.

Ducky2003 profile image
Ducky2003 in reply to Visigoth

I was put on Amiodarone, initially, for 3 months prior to DCCV number 2 and this kept me in NSR (number one only lasted 4 days). I stayed on the Amiodarone as I was supposed to have an ablation previously but I had kidney issues then got missed off the list when my then consultant left the hospital. New consultant tried taking me off Amiodarone and I lasted 8 months in NSR and then AF again and DCCV number 3 and on the ablation list. He then tried halving the Amiodarone dose and then back into AF after a few weeks so back up to full dose and, eventually, DCCV number 4 and ablation expedited. I have been told to continue the Amiodarone up to the procedure and as far as I'm aware, I will have to take it for a few weeks following...... obviously, that may change. I wish I hadn't got to have an ablation but I've exhausted all of the non invasive routes so here I am. Will post how things go.😊

Visigoth profile image
Visigoth in reply to Ducky2003

Thank you! I shall watch out with interest!

Hello, I took Flecainide 2 years ago and I was on it for only a week! It helped with my arrhythmia, but I ended up having 80% of the side effects Flecainide can cause!! Talking about scary! Then my EP doctor tried to get me to take a low dose of it because they were happy it was controlling the arrhythmia, BUT wasn't too concerned about the side effects! I had to stop taking it! Now, if I have troublesome palpitations, they want me to try another arrhythmia drug called Tikosyn. With that, you have to stay in the hospital for 3 days to get monitored, but I'm not going to complain about that! In my opinion, all drugs that deal with the heart, and the rhythm of the heart, should be monitored closely when you first start taking them! When you started taking Flecainide, they should have told you about other options you wanted to look into.. Sorry that it caused you to have more arrhythmia to happen, but I read that one of the possible side effects is arrhythmia!! I hope you can find a drug that is right for you!

Poochmom profile image
Poochmom in reply to MsBlessed73

Thank you so much for your reply. I hope I can get one that works also. I love this forum. It has been so positive for me and the anxiety that I’ve experienced from all of this.

Karendeena profile image
Karendeena in reply to Poochmom

I'm with you on that Poochmom x

Flecainide did not suit me and on a low dose was manageable (50g twice a day ) but as soon as they put me on 100g twice a day I was back in hospital with a major attack and they took it off me immediately. You dont need to be on it as there are other drugs. Ask for another drug.

Poochmom profile image
Poochmom in reply to mobradley

Thank you! That is what I plan to do. I will not take the Flecainide.

I wish I knew what “constant arrhythmia” felt like as Dr Google just says fluttering or fast heartbeat or fainting or dizziness. I hear / feel a “grinding sensation 24/7. It also feels like my left side is pulsing a billion miles an hour. Usually kickd in after eating. I get no sensation in heart unless it’s an irregular heartbeat (wild swings). Have passed out twice. It all started with bouts of dizziness on standing or bending. Always had very low BP. A loop monitor revealed I have intermittent aFIB. I was put on 40mg x twice daily of Sotalol. It’s been less than a month and was sooooo fatigued I decided last week to halve it eg: only taking 40mg a night. Like the postee I guess we’re all not cut out for the same drug and should change them until one works best!

Palpman profile image
Palpman in reply to AussieHeart

Sotalol lowers blood pressure and pulse rate and as you already have low BP you may feel faint. You should check your own bp to get more accurate readings.

Poochmom profile image
Poochmom in reply to AussieHeart

Thanks aussieheart. I define flutter as when it skips a beat then extra beat. Happens off and on.

Can you check the dose of your Flecainide cause you mentioned in your comment that you are taking 5 mg. The dose preparation of Flecainide are 50 mg and 100 mgNow sinceFlecainide is anti arrythmic , it also has a proarrythmic effect. The effect of it varries to a different patients. You may consult back your attending doctor for some revision of your prescription drugs.

Poochmom profile image
Poochmom in reply to RTA_25

Hi. Yes it’s 50 twice a day but I’m not currently taking it. Plan on talking to cardio but waiting for a call back.

Hi Poochmom, happened to me exactly the same, had awful arrythmias with fast heart rate, the very condition it was supposed to treat! I paid to see a top EP privately and he told me flecainide wouldn't have been his first choice for me and changed me to Sotalol and I am much better on this. I still get the odd afib episode but nothing like I had on flec. Hope this helps

Poochmom profile image
Poochmom in reply to Karendeena

Thank you fir the validation!!! Appreciated.

Hi poochmom when I was in my first bout of persistent AF I was put on a low dose of flecanide & boy was it horrendous. From taking the very first tablet I had every side affect going. Insomnia, didn’t sleep for 3 days, sickness, muscle spasms continuously, headache etc. When I told EP he stopped it straight away but didn’t put me on anything else. Wish I was one of the lucky ones who can tolerate these type of meds. Hope you get sorted soon. Ps I’m now 5wks into 2nd episode of persistent AF & waiting for cardioversion & another ablation.

Poochmom profile image
Poochmom in reply to Van28

Can I’m so sorry you are so far into an attack. They are awful. I hope you get relief soon. I don’t know what my cardio will say but it’s not going to be Flecainide. We will see. Thanks for your reply

It seems to be just getting the balance right. You defo need to establish communication links with the cardiac team. I do it through Cardiac nurse at specialist hospital.Everyone is different. I take 100 mg of Flecainide but has been adjusted several times and balanced with other medications.

Poochmom profile image
Poochmom in reply to Mawes

Thank you so much.

I am reading this thread with interest :-) now I have had my second dose of vaccination and am soon able to have someone with me when I take my first dose of Flecainide (which I agreed to do having declined the offer of hospital) I will shortly be able to give it a try.

I think my P-AF is certainly getting worse, 2 weeks ago an episode lasted 20 hours and there have been other long episodes since . I am prepared for the fact it may not suit me but will give it a number of days in the hope it will will help what is now becoming a quality of life issue after 4 years of hard work in which I may have managed to postpone the progression of P-AF with lifestyle changes .

Oh dear are you sure it is the flecainide ? 5mgs sounds a very low dose. I take 50mgs twice a day and have been on it since January and touch wood so far it has been good for me. However I have heard a few adverse things about it so hope your EP can sort you out All the best

Flecainide caused me to have a near fatal VT. Heart rate went to 280bpm and almost caused a cardiac arrest. I know lots of people have no problems with it so it really is a case of finding what works for you. I am now on sotalol z

Ditto. Did the same to me. Switched to Multaq which barely works but Flec a very strong drug.

My arrhythmias got worse on 50mg x 2 Flecainide so it was increased to 100mg x 2.It was fine since for 2 years.

Agree with your thoughts and inclinations. I had a similar sequence of interventions. Holter, stress tests, then ghastly, dizzying beta blockers etc. Averaging 17 mis-beats per min. I gave up on symptom-suppression medication in the end and attacked the obvious cause; poor heart health. Changed my diet and eased into what gradually became quite an impressive cardio exercise regime. I have no idea why doctors don't encourage such a solution!

I use sotalol as it is the only one that helps me. Tried different tablets but they made me so tired. I had three ablations so now only take a tablet if I have an AF attack .

Poochmom profile image
Poochmom in reply to g00dfellow

Thank you. I will take note of these other meds.

cuore profile image
cuore in reply to g00dfellow

Fantastic! Three ablations and you are not taking anti-arrhythmic med except sotalol as a PIP. I have also had three ablations and did try coming off Propafenone only to go into persistent AF. I'm having a cardioversion in two days.

g00dfellow profile image
g00dfellow in reply to cuore

Good luck. My last ablation , my heart was pierced ....a bit of a drama there.

cuore profile image
cuore in reply to g00dfellow

Thank you goodfellow. I had a successful cardiovrsion and I am now in sinus.

I have not heard of the heart being "pierced" during an ablation. Do hope you have recovered.

I found flecanaide not suitable and went on to Sotalol but most important is to be a on an anticoagulant to prevent strokes with AF

Poochmom profile image
Poochmom in reply to Bruceyboy

Hi Bruceyboy. Thank you for your reply. I on an anticoagulant and have been for two years. I have read about good things with the sotalol. I can’t seem to get communication from my cardiologist. I have decided I’m going to see an EP to try and at least get on a regimen to maybe get this on a level playing field. It’s so frustrating.

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