What Is Propafenone, How Does It Work, And What Are The Risks/Side Effects?

— -- Question: I have been placed on an antiarrhythmic drug called propafenone for my heart rhythm problem. How does it work and what are the side effects?

Answer :Propafenone is a very commonly used heart rhythm drug. It's a sodium channel blocker and it's kind of a first cousin to another heart rhythm drug that you may have heard called flecainide.

This drug differs a little bit than flecainide although it has some similarities. It also has a little bit of beta blocker in the drug. Beta blockers are drugs that block adrenaline to the heart.

This drug is predominately used in people that have strong hearts with minimal problems to the heart because if you have a structurally abnormal heart, for example if you've had a heart attack and a weakening of your heart muscle, or a virus to your heart with a weakening of the heart muscle, this drug can worsen rhythms and we usually do not use that in such patients.

This drug works very well when properly selected. Its main side effect are that sometimes it can cause some headaches and some people get a funny, metallic taste in the mouth. But usually from a subjective standpoint -- that is how the patient feels -- they have very little problems in taking this medicine.

Most of the time that it is discontinued is because it either doesn't work, or there are changes in some of your EKG measurements that your cardiologist may be concerned about and decide to put you on a different medication.