PiP

I have afib episodes every couple of days. At that point I take 100mg flacainide and go back to NSR within a few hours. I read in a recent post that that individual was told by his doctor to wait several hours to see if it converts and only then take the medication. Any thoughts?

There's no reason to wait. Maybe that person had some special circumstances?

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alfrae13
I have afib episodes every couple of days. At that point I take 100mg flecainide and go back to NSR within a few hours. I read in a recent post that that individual was told by his doctor to wait several hours to see if it converts and only then take the medication. Any thoughts?

1. Have you successfully converted on your own in the past? If so how long did it take to convert? If many hours or longer, I don't think it would be something I'd do.
2. Given you are getting episodes frequently, perhaps taking the flec prophylactically.

A brief history for me. I got afib 19 years ago and for the first two months after getting it, was getting episodes every 10-14 days for 6-9 hours. These would convert on their own or with exercise. Then at two months, had an episode that didn't convert for 2 1/2 months and that was converted by 300 mg PIP flecainide. By moderating my exercise and adding in taurine, magnesium & potassium supplementation, I was getting just a few episodes a year. These were converted with PIP flecainide. 10 years ago I'd added in additional calcium from food and my episode frequency increased. Figured out the calcium piece, and reduced calcium intake to 400-500 mg/day and episode frequency went back to a couple of times a year. More recently, I had an association of increased frequency with C19 vaccines. I started taking 25 mg flec once a day, which worked very well (even though most EP's and the data from studies would tell you it would not work). If I pushed my boundaries of known triggers, I could still take a 200 mg flec PIP dose and convert. This worked very well. I hypothesized if I stayed away from C19 vaccine boosters long enough, I'd be able to quite the flec. On June 9, 2023, I was about 8 months out and decided to try. So I cut my dose to 12.5 mg/day for 15 days & then 0 for the last 4 weeks.

I tell this story as you might ask your doc about starting low (25 mg/day or 25 mg 2x/day) and and seeing if this dose would keep you out of afib altogether. Given you only need 100 mg to convert, seems like you'd still have plenty of room to use a PIP dose to convert if the experiment failed. Again, see if your doc would approve this.

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GeorgeN

... Given you are getting episodes frequently, perhaps taking the flec prophylactically...

Yuupp! If you're having to take medication to nip frequent episodes, you shouldn't be doing PiP. You should be taking perhaps 25 mg BID, or twice that amount. And while you're still paroxysmal, beat the bushes for a really good electrophysiologist and get on his/her Christmas list. You should want an ablation as soon as possible if you're a candidate at all, but certainly before you leave the paroxysmal evolutionary stage.

I already tried this. At 50mg 2/day nothing happened. When I increased to 75mg 2/day I became woozy,and did not feel well. Thats when I switch to PiP and started with the lowest amount. At present it works

I already tried this. But PiP works at present and converts in just a few hours. My motto if it works don't change it

Let me chime in by saying the maximum flecainide dosage in a 24 hour period is 200mg if you weigh less than 154 pounds. If you weigh more than the maximum dosage in a 24 hour period is 300mg. Flecainide is not a drug to experiment with. I suggest you ask a qualified EP first.

It depends on your individual pattern.

If you frequently convert within a couple of hours, then that advice makes a lot of sense. Why take the extra Flec if you don't have to? Plus the Flec usually takes 1-4 hours to kick in anyway, so overall you're not shortening your afib episode any by waiting a couple of hours.

On the other hand, if you tend to remain in afib longer than a couple of hours, then take the PIP dose right away, or maybe wait 10-15 minutes like I used to, just in case it was really a short episode.

PIP dosing doesn't have to be set in stone but something that can evolve as you learn how your heart behaves in afib. Of course, your doctor should be on board with whatever you do.

Jim

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mjamesone
It depends on your individual pattern.

PIP dosing doesn't have to be set in stone but something that can evolve as you learn how your heart behaves in afib. Of course, your doctor should be on board with whatever you do.

Jim

Unfortunately not all EPs are equal. My EP at the time told me to increase to 300mg a day until I had an v-tach episode in his office and almost died in the ICU. Flecainide is not a drug one should experiment dosage with based on “how you feel your heart will behave”. By then it could potentially be a fatal mistake. There are dosage guidelines for a reason. Flecainide is a black box drug.

You can ask others who have been on this forum a while that I will always post about flecainide overdose potential risks as a public service when this topic is discussed. You can read more from this link discussion.
[www.afibbers.org]

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susan.d
Flecainide is not a drug one should experiment dosage with based on “how you feel your heart will behave”. By then it could potentially be a fatal mistake. There are dosage guidelines for a reason. Flecainide is a black box drug.

Sure, but experimenting with a lower dose is a whole different thing than on the high side. I recently got a friend (with his EP's approval) to drop his chronic flec dose to 75 bid from 100 bid. He may now (after consulting with his EP) try 50 bid. If a med is working, I don't think most docs give a lot of consideration to finding the minimum effective dose.

George- I meant experimenting with dosage levels higher than recommended— <154 pounds=200mg maximum in a 24 hour period, and >154 pounds is 300mg dosage in a 24 hour period…nothing wrong with an Ep recommendation to experiment within recommended dosage range.

I like the flecainide serum lab test. I had it done twice before and after weight loss. Blood is drawn exactly 11 hours after your last dose which aids in determining your levels remaining which aids in an individual dosage.

The issue with maintaining your flecainide levels is its result on one’s liver enzymes processing flecainide out of your system. Plus CYP450 inhibitors affects on liver enzymes of drugs interactions that may increase your flecainide levels…such as if one takes something as benign as a supplement (echinacea, milk thistle, for example) or taking interacting drugs that may affect your enzymes resulting in higher flecainide levels.

I previously posted labs that do flecainide serum testing.

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susan.d
]
I previously posted labs that do flecainide serum testing.

But don’t assume your doctor will do this test or even be WILLING to do this test!

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Daisy
But don’t assume your doctor will do this test or even be WILLING to do this test!

As I posted here, I figured out from inadvertently taking a PIP dose of expired flec that my 300 mg dose of flec was too high. My hypothesis was that the expired flec had lost around 1/3 of its potency. The experiment I wanted to run was to consume 300 mg of the expired flec, then get my serum level tested at 3 or 4 hours after consumption. Wait for a week or so to get all the flec out of my system and consume 200 mg of newly purchased flec, get the serum level tested at the same number of hours after consumption. As I recall, the test I planned to use was through LabCorp. I tried to get the test added to a third party testing provider's catalog, but they told me LabCorp denied their request. I know enough docs, I probably could have gotten one of them to prescribe the tests (they know I do unusual things), but I never followed through. Instead I just took 200 mg of newly purchased flec the next time I had an episode and got the same improved response that I'd gotten taking 300 mg of the expired flec. I've repeated it twice for two episodes since with the same results so don't have any motivation to jump through the hoops to run my experiment using the serum test.

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Daisy
]
I previously posted labs that do flecainide serum testing.

But don’t assume your doctor will do this test or even be WILLING to do this test!

why not? Are they not on your team in being your advocate? What’s the harm in granting a lab test?
I was fortunate to pick a doctor who was helpful and humored me.

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susan.d
why not? Are they not on your team in being your advocate? What’s the harm in granting a lab test?
I was fortunate to pick a doctor who was helpful and humored me.

It could challenge their expertise in choosing the right dose for you.

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Daisy

why not? Are they not on your team in being your advocate? What’s the harm in granting a lab test?
I was fortunate to pick a doctor who was helpful and humored me.

It could challenge their expertise in choosing the right dose for you.

Daisy, I want to share an experience regarding getting the best expertise. My original EP suggested on his own to test me in 2004 to determine the correct dosage. I was overweight. Then I shed (too embarrassed to say how much) a lot of weight and I was testing again to determine at my lowest weight if my initial flecainide dosage was still safe for me.

Then I switched out of my HMO and in 2019 choose another local EP near me. I weighed 121 pounds and he suggested I try 150 BID (300mg a day) and after five days to come in for a stress test to determine if the higher dose was safe. I asked him why not take a serum test first? He didn’t want to do the flecainide serum test. I increased to 300mg as he advised because I thought he was qualified. Needless to say during the stress test I went into v-tach. He stopped the test and replied he got his answer, the increased dosage was not safe for me.

A simple serum test perhaps could had told him that, or maybe not…I will never know. But I think about this from time to time and regretted not being my own advocate and pushed more for the lab test.

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Susan.d.
A simple serum test perhaps could had told him that, or maybe not…I will never know. But I think about this from time to time and regretted not being my own advocate and pushed more for the lab test.

I was also overdosed on Flecainide by an EP who was confident in they dose they had prescribed. I got complete heart block, so I understand the danger.

When flecainide stopped working for me, my doctor ordered the following test for me to see if my flecainide dose could be raised.
The lab was performed at Quest Diagnostics.

FLECAINIDE (TAMBOCOR)
Your Value
1.13 mcg/mL
Standard Range
0.20 - 0.99 mcg/mL

Since my value was higher than the range, she did not raise the dose.

Flecainide serum test FYI
[testdirectory.questdiagnostics.com]

Info about the test:
[account.allinahealth.org].

Mayo also tests:
[www.mayocliniclabs.com]

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Pixie
When flecainide stopped working for me, my doctor ordered the following test for me to see if my flecainide dose could be raised.
The lab was performed at Quest Diagnostics.

FLECAINIDE (TAMBOCOR)
Your Value
1.13 mcg/mL
Standard Range
0.20 - 0.99 mcg/mL

Since my value was higher than the range, she did not raise the dose.

Generally the trough (lowest level during the day) level is sampled. I've attached a paper describing a study. Per the bolded section (my bolding) in the abstract below, your 1.13 mcg/mL (aka 1130 ng/mL) is certainly too high.

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The reported therapeutic range for trough flecainide concentration is 200–1000 ng mL--1. Severe adverse events, such as ventricular arrhythmias, have occurred occasionally in patients whose serum flecainide exceeded 1000 ng mL--1. However, the lower limit remains controversial. We have evaluated blood flecainide concentrations in patients with tachyarrhythmia who received the drug to control palpitation. We measured the flecainide trough levels and incidence and frequency of palpitation of 44 outpatients receiving oral flecainide (150–300 mg daily). Mean serum flecainide trough concentrations differed significantly between patients with (n = 14) and without (n = 30) palpitation (259.5 – 85.2 vs 462.2 – 197.7 ng mL---1, P < 0.01). The frequency of palpitation decreased as the serum flecainide concentration increased. The incidence of palpitation was 65% at serum flecainide concentrations < 300 ng mL--1 and 11% at ‡ 300 ng mL---1. QRS values were increased significantly in patients with serum flecainide ‡ 300 ng mL--1 compared with < 300 ng mL---1 (0.110 – 0.016 s vs 0.093 – 0.019 s, P < 0.05). We concluded that to control paroxysm in patients receiving flecainide for tachyarrhythmia serum flecainide concentrations should be maintained at ‡ 300 ng mL--1.

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susan.d
Daisy, I want to share an experience regarding getting the best expertise. My original EP suggested on his own to test me in 2004 to determine the correct dosage. I was overweight. Then I shed (too embarrassed to say how much) a lot of weight and I was testing again to determine at my lowest weight if my initial flecainide dosage was still safe for me.

Then I switched out of my HMO and in 2019 choose another local EP near me. I weighed 121 pounds and he suggested I try 150 BID (300mg a day) and after five days to come in for a stress test to determine if the higher dose was safe. I asked him why not take a serum test first? He didn’t want to do the flecainide serum test. I increased to 300 mg as he advised because I thought he was qualified. Needless to say during the stress test I went into v-tach. He stopped the test and replied he got his answer, the increased dosage was not safe for me.

A simple serum test perhaps could had told him that, or maybe not…I will never know. But I think about this from time to time and regretted not being my own advocate and pushed more for the lab test.

I posted above about figuring out that my PIP dose of flec was too high. When I was first diagnosed and prescribed 300 mg PIP flec, I weighed 205# (93 kg). As part of my afib remission plan was to detrain endurance activity, my weight started increasing. I changed my eating plan a couple of years after and ultimately dropped down to 168 #'s (76.4 kg), which I weigh today. Note this is still above the 300 mg flec cutoff of 154 #'s (70 kg). What I was experiencing was conversions to what I assumed was flutter (not 1:1) after taking PIP flec during afib. Until I accidentally figured out the flec could work better at a lower dose, I was assuming flec was starting not to work well for me and was thinking about ablation.

As I've also previously posted, during the last few years, I started taking 25 mg/day of flec, on a chronic basis. Per data from the attached study, and others, it would indicate that 25 mg/day would not be useful. Yet it was, in my case. It would have been interesting to know what my serum flec levels were.

Thanks George! I wish I had your link info 2019. Still handy for those readers considering either a PIP or a general daily increase— to consider first taking the serum test.

I did try to wean myself from 100mg BID to 75mg BID years ago after my big weight loss thinking weight-wise perhaps I didn’t need the same dosage as pre-diet. I went into afib so I went back to 100 and I remained in nsr.

I thank you too, George. Needless to say, I which I had known then what I know now, thanks to all of the information I learned from folks on this forum!

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GeorgeN
I recently got a friend (with his EP's approval) to drop his chronic flec dose to 75 bid from 100 bid. He may now (after consulting with his EP) try 50 bid. If a med is working, I don't think most docs give a lot of consideration to finding the minimum effective dose.

Just talked to my friend I mentioned above in the quoted post, he has successfully dropped his dose to 50 bid. He may try to go even lower.