Why are antiarrhythmic drugs dangerous?

They suppress arrhythmias but can cause new ones?! I just started taking berberine, a herb with class III antiarrhythmic properties. Now, I'm only having like 1 PVC per day (which is great!), but that little voice in my head is telling me that I could get hurt. Should I listen to that voice or tell it to shut up? What could happen? QT prolongation? V-tach? Death?

[dolfnlvr]

Mainly, you need to talk to your doctor about this.  Herbs and supplements are not regulated by the FDA and, given the recent news that some things that ARE regulated by the FDA aren't so well regulated, I'm always nervous about completely UNREGULATED products.  

I took Norpace for awhile.  It is a heavy duty antiarhytmetic that suppresses the sodium and potassium channels causing the pacemaker cells to fire more "regularly."  Unfortunately, since pacemaker cells (all muscle cells) contract based on the concentration of sodium and potassium in and around the cell, this medication can cause serious "confusion" for the cell and may result in a very serious arhythmia.  When you are put on norpace for the first time, a cardiologist will usually admit you to the hospital for the first 48 hours to monitor heart rate and ensure that your cells will not react negatively to the medication.  If you "pass" the first 48 hours there is a good chance that your cells are well adjusted to the shift in sodium/potassium levels and have regulated their cycle of polarization/depolarization to fire at regular intervals.

In other words...these drugs interfere with THE NUMBER ONE MOST IMPORTANT MECHANISM IN CARDIAC MUSCLE CONTRACTION.  That means that it is messing with some pretty important stuff and you need to be monitored for side effects.

Since NORPACE (disopyramide) is a regulated FDA drug, it is well studied and the risks are clearly apparent.  Berberine is not well studied and you are relying on the anecdotal evidence of users instead of scientific data to make your decision and adjust your dosage.  Antiarhythmetics are monitored on a case by case level because each persons biochemistry is unique and the drug does not have the same effect, or even a particularly "normal" effect on all that take it.

Moral of the story....be careful and seek the advice of your doctor.

April

[Momto3]

Ditto on everything dolfnlvr said!  

I took antiarrythmics for about 7 months....and YES, they absolutely have some potentially serious side effects.  I was started on the medication in the hospital.  I was in the telemetry unit for 3 days with 24 hour monitoring.  Yes, a change in the QT interval is a definite possibility - happened to me.

Talk with your doctor about how to manage the symptomatic PVCs.  It's not worth taking the chance of guessing what "might" help.

[Hopeful39]

Extremely good advice given above.  I work in the clinical medicinal industry where we manufacture drug products for experimental investigations that often end up as first in human (FIH) products.  Three things are very, very important for all of us.

1.  Discuss all drug products (and especially combinations that you are prescribed simultaneously). with your cardiologist, GP, or any other learned intermedairy (health care provider) that is responsible for your health.

2.  Do your own research.  What ever you discover on your own, use this a basis for conversation with your health care provider.  

3.  Be very careful about any product intended (or with a label claim) to have a pharmacological effect on the body that is not approved by a regulatory body (e.g. FDA for U.S.A., EMEA for Europrean Union).

Wishing you well.

[janetls]

It's paradoxical, but anti-arrhythmic drugs can cause arrhythmias.  Just like chemotherapy drugs can cause cancer.