Skip to content


    Exciting News for WebMD Members!

    We've been busy behind the scenes building new message boards for you. You'll have new and easier ways to find messages, connect with others, and share your stories.

    And, this will all be available on your smartphone or other mobile device!

    What Do You Need to Do?

    The message board you're used to will be closing in the coming weeks. While many of your boards will be making the move to our new home, your posts will not. Want to keep a discussion going? Save posts you want to continue (this includes your member profile story), so that you can re-post them in the new message boards.

    Keep an eye here and on your email inbox, we'll be back in touch soon to give you all the information you need!

    Yours in health,
    WebMD Message Boards Management

    Flecainide and QT intervals
    anonymous854 posted:
    From what I've read, Flecainide typically prolongs the QT interval. However, mine has decreased from around 440 to 400. I've ready that this is suggestive of LQTS but I have never had a long QT reading. Is this shortening normal of Flecainide? It has slightly prolonged all other intervals on my ECG.
    cardiostarusa1 responded:

    "Is this shortening normal of Flecainide?"

    It may/can have this effect, as reported, in some individuals under certain or specific circumstances.

    Randomly-selected info (contains med-speak)

    Long QT syndrome

    Emerging treatments


    Flecainide is a class IC anti-arrhythmic drug with potent sodium channel-blocking properties. Patients with LQT3 mutations have an abnormal sodium channel allowing an inward current to persist long into the plateau phase of the potential, thereby prolonging the QT interval. In these patients, flecainide has been shown to shorten and even normalise the QT interval......

    (Access to content may require a subscription)

    For those not familiar with the QT interval.

    QT interval (includes info on prolonged QT)

    Best of luck down the road of life.

    Take care,


    WebMD community member (8/99)



    It's your there.


    WebMD/WebMD forums does not provide medical advice, diagnosis or treatment.
    anonymous854 replied to cardiostarusa1's response:
    Can this be normal in those without LQTS as well, as I have never had a long QT??
    cardiostarusa1 replied to anonymous854's response:
    It may/could be, as anything medical is seemingly possible today, especially when it comes to the heart's electrical conduction system, and the various effects on it.

    Take good care,




    Be well-informed

    Heart Rhythm Society

    Patient and Public Information Center


    LEARN ABOUT the Heart


    The Heart: (Human Anatomy) Pictures, Definition, Location in the Body and Heart Problems


    It's your there.

    Helpful Tips

    Nix Grapefruit & Statin DrugsExpert
    Grapefruit & statin drugs can be a bad combination. Unlike other citrus fruits, grapefruit contains substances that disable certain ... More
    Was this Helpful?
    17 of 19 found this helpful

    Expert Blog

    The Heart Beat - James Beckerman, MD, FACC

    Dr. James Beckerman shares how small, livable lifestyle changes can have a real impact on your risk of heart attack and stroke...Read More

    Related Drug Reviews

    • Drug Name User Reviews

    Report Problems With Your Medications to the FDA

    FDAYou are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

    For more information, visit the Duke Health General and Consultative Heart Care Center