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Flecainide side effect I hadn’t expected!

Sunnyday2022 profile image
24 Replies

I have finally had to give in and start taking Flecainide albeit at a low dose with a larger dose as a PIP option.

I had very slight dizziness for the first couple of days which soon wore off and there is nothing else of note apart from the fact that I have started with quite pronounced constipation which isn’t great :(. I have upped my intake of fibre, water etc but to no avail, even taking a bit of senna (which I am loathe to do) isn’t helping much.

I know many of you have been on Flecainide for a while and I wondered anyone else has had this problem? If so did it wear off after a while like many side effects do or was it persistent? I would like to know before raising it with my cardiologist as I don’t want to waste his time or patience if it is unrelated (though it does seem a pretty big coincidence!).

I would be grateful for any advice. This forum is so helpful at being able to raise issues like this with fellow members of the AF community and I am so grateful to have stumbled across it :)

Happy Friday and keep warm everyone!

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Sunnyday2022
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24 Replies
CDreamer profile image
CDreamer

it is a side effect I’m afraid - hydration - more water than you think you need, exercise and 2-3 prunes/day. Listen to the Zoe Podcast on the subject - excellent

joinzoe.com/learn/podcast-t...

Sunnyday2022 profile image
Sunnyday2022 in reply toCDreamer

Thank you for that I will do. Seems like it is going to be an ongoing problem and I don’t want to have to take laxatives unless I really have to! Heading for the water jug now 🤪

Dippy22 profile image
Dippy22

I was just about to post about this dehydration problem myself!! I’ve been severely dehydrated since starting taking 50mg twice a day around the end of January. I’ve just read a paper online that’s it’s an uncommon side effect - especially in women aged 60+. I’ve never had a problem with constipation before, but having been living on laxatives ever since. I bought some urine test sticks off Amazon for a tenner, which confirmed the chronic dehydration.

I’ve just had a spinal fusion op and the dehydration was a HUGE issue post-op causing my BP to bottom out. Drinking 3-4L of fluids made NO difference - it just went straight through. It seems I’m totally unable to hold fluid in the body tissues.

I’ve got a call out to the (private) cardiologist about it, but getting the so and so to respond is like getting blood out of a stone!!

This is a real problem people!

Sunnyday2022 profile image
Sunnyday2022 in reply toDippy22

Hmm it is very frustrating.

Interestingly I had spinal surgery a couple of years ago (pre Afib times) and also had a major problem with dehydration leading to very low blood pressure. I was then on codeine for post op pain which also causes constipation issues but at least that was only for a week or two whereas the Flecainide is long term 😫

CDreamer profile image
CDreamer in reply toDippy22

Prunes - at least 2 per day. Prunes have an interesting affect in the bowel - they draw water to to bowel thus easing the problem. I have very low BP - always have had - so I need to drink at least 8 glasses of water/day and then normal tea (herbal) & one coffee. Coffee after breakfast helps constipation I found.

Threecats profile image
Threecats in reply toDippy22

That’s really interesting about the dehydration side-effect, I missed that one! I have noticed, about an hour or so after taking it, that the skin on my fingers and backs of my hands goes all wrinkled, as if I’ve had them in water for too long. I thought I was imagining it at first but it’s happened repeatedly now.

As you say Dippy, trying to get any further advice out of the private cardio is nigh on impossible, even though he prescribed the drug in the first place🙄

Threecats profile image
Threecats

Hi Sunnyday (like the name- we could do with some of those😊)

I started Flecainide 50 mg twice a day just over a week ago and have the same problem. Things have always been a bit slow in that department but now they’re positively glacial 😳 I’ve upped my daily prune intake and also changed my magnesium to magnesium citrate for a while to see if that does the trick. As CDreamer suggests, I’ve also upped my fluid intake, too. Here’s hoping!

Sunnyday2022 profile image
Sunnyday2022 in reply toThreecats

So we are in the same boat! I will try to same as you and hope things improve 🤞

wilsond profile image
wilsond

Im the odd one out I think! I get IBS and flec has helped no end with the opposite effect. I know where all the public loos are/ friendly cafes🙂😀But above advice can only helpxxx

CDreamer profile image
CDreamer in reply towilsond

😱 mind you I’d rather be on that end of the spectrum to be hones - I used to have problems both ways - as you do with IBS or Colitis but thankfully I’m mostly through those stages now so only have the odd upset.

Bodydoctor12 profile image
Bodydoctor12

hi, how about trying a tablespoon of chia seeds soaked in water - with a squeeze of lemon - stir it and drink an hour before bed. Give it a few days - it might help.

Regarding water - if your water regulating hormone balance is out of whack then it doesn’t really matter how much water you drink, it’ll flush through you! I found that out years ago and I see an endocrinologist in Brussels who’s helped me rebalance them. I take a supplement each day and now have no issue with excessive peeing and constipation.

doodle68 profile image
doodle68

Hello Sunnyday, the first time I took Flecainide having been prescribed a twice daily dose of 50mg, I experienced blurred vision, loss of balance,headaches and eventually increased extended episodes of AF . So it did nothing to help my AF and after taking it for a while I discontinued it . I believe the dose was wrong for me and I would have been better taking a larger dose earlier as a PIP having first tried it under supervision.

Many doctors recommend a first dose of Flecainide in hospital where dose and reaction can be monitored but I was scared to go to hospital when my episodes became more frequent because I also have asthma and was very scared of catching COVID. So with my AF even more active not wanting to wait any longer to try it I saw an EP privately, paid for an Echo and I was allowed to try a small dose at home.

I was asked to try Flecainide again in January because my AF has progressed , this time the side effects were even worse with my wanting to black out many times a day and a 10 day episode of AF so I stopped it again and am on a long waiting list for an Ablation. I asked about taking a dose as a PIP now and was told it was too late because my episodes were too close together (I am in AF more than not ) and it would mean I would be taking a larger dose most of the time.

On one occasion recently in desperation when an episode started I took Flecainide as a PIP, lay down and the episode stopped within an hour. My AF was back the next day.

I don't think anyone should judge Flecainide on the experience of others, we are all different and need to try it for ourselves preferably the first time under close supervision to gauge a correct dose. Also it is best to try Flecainide before episodes become too long and frequent .

Profound15 profile image
Profound15

I’ve been on flecainide 50mg twice a day for two and a half years. I also take one bisoprolol 1.25mg. I too suffered from constipation but take laxido once every two days and four prunes with a half cup of prune juice which seems so far to do the trick. The unfortunate side effect of prunes and laxido is gas unfortunately but it’s better than being constipated.

Tapanac profile image
Tapanac

I too am on flecainide but I’ve had bouts of constipation all my life and have found no difference since taking flecainide

However I have had a long bout of constipation recently snd I found from the supermarket home baking section 4 soft prunes, 1 soft fig, 1 soft apricot taken in the morning (I never have breakfast but this takes it’s place and quite pleasant). If then bowels become slightly urgent I cut down to 3 or 2 prunes

Good luck

Pat x

Sunnyday2022 profile image
Sunnyday2022 in reply toTapanac

Hmm everyone seems to be recommending prunes! I haven’t had them since I was a child (a long time ago 😂) and I hated them then but I will certainly give all the suggestions a try. Thank you

Tapanac profile image
Tapanac in reply toSunnyday2022

the soft ones are actually not too bad. I’ve never liked them before, but the soft figs, prunes snd apricots aren’t bad at all

Have a go and give them a few days to get into your system.

All the best x

Sunnyday2022 profile image
Sunnyday2022 in reply toTapanac

Thanks I will try mixing them in with my normal yoghurt and berries breakfast and see how I go!

frazeej profile image
frazeej in reply toSunnyday2022

Based on first hand knowledge, start off slowly with prunes/prune juice. Prunes and the juice contain large amounts of "sorbitol", a naturally occuring sugar that is metabolized quite differently in the gut from other sugars-as a result, sorbitol is a powerful laxative, with some folks having very urgent and rapid effects! An 8oz. glass of prune juice contains >15gm sorbitol, and some folks respond to around a 5gm dose. So, go slow! Personally, without going in to details, I found this unexpected "urgency" to be a far greater problem than the constipation, and have adjusted "dosing" appropriately.

petmice profile image
petmice in reply toSunnyday2022

I haven't had them in decades either but thanks to your post and one other (you aren't the only one who finds a connect between flecanide and constipation) prunes and prune juice went on next week's shopping list. :)

tunybgur profile image
tunybgur

I'm on flec but have no constipation issues.

Constipation is often caused by a problem with the gut microbiome, a result of our modern life and diet, and if you've had antibiotics recently they can decimate your gut bacteria.

I regularly take probiotics to keep the gut working properly, a glass of home made kefir every day and sauerkraut or similar with meals. Yoghurt is also good but many commercial ones have too much sugar and too little live culture.

Better to fix the root cause.....

Good luck

Hdev profile image
Hdev

Within 2 weeks of starting Flecanide,,I too had an issue with C! Despite adding fiber and keeping up with fluid intake,,,I had 2 severe rectal bleeds in that 2 week period,,almost sent me to the ER both times ,,,on Eliquis too so the bleeds were serious,,,I was taken off Flecanide,,,and remain only on metoprolol and Eliquis for afib,,,not an answer as my afib is gradually increasing in frequency,,not sure what the next step is,,my neck EP appt is April 3

ramblerbaz3 profile image
ramblerbaz3

Hi

I also had constipation whilst taking Flecainide & found Magnesium Citrate did the trick. When I stopped the magnesium for a while, the constipation came back.

I just take half of the recommended dose (1 capsule) & all ok again.

Good Luck !!

Sunnyday2022 profile image
Sunnyday2022 in reply toramblerbaz3

I do take magnesium citrate already to help with sleeping but will check dosage so thanks for the info!

fabjabfab profile image
fabjabfab

Sadly I experienced the exact same thing, prunes helped me and I did a couple of enemas which got things moving. My dizzy spells did not subside sadly so I had to change to Propafenone.

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