Drug interactions?

[amangang1]

I am currently on flecainde acetate 100 mg twice a day for Ectopic Atrial Tachycardia. Recently I also started taking Lamisil to treat a nail infection in my thumb. When I started the Lamisil, my doctor decreased my Flecainde dose to 50 mg twice a day. However, this dose is ineffective in treating the arrhythmia. I tried taking propranolol to help, and it works, but it makes me very tired and depressed. So I called my doctor, and he said I could try the 100 mg twice a day, but to have an EKG done a couple weeks after starting back.

My question is this: The side effects from the flecainde (in my case, mild vision problems and my tongue goes slightly numb) seem to be a little stronger, and last longer than usual. Also, I can feel some electrical things going on at times when I'm normally fine. Is there some sort of negative reaction going on? And if my regular side effects are inensified, could there be other things going on? If there were an electrical problem based on drug interactions, how would I know if it's that, instead of just the EAT that I already have?

Thanks for your help.

[Dr. Chan Lowe]

Lamisil is known to increase blood levels of flecainide. Generally when Lamisil is needed, the flecainide dose can be decreased.

It appears that in your case, the decrease was too little of a dose, but the increased dose was leading to side effects.

Your side effects may actually be from the Lamisil rather than the flecainide. Lamisil is reported to cause some taste changes and vision changes.

You may wish to talk with your doctor about a different medication to treat your nail infection.

Regarding the electrical problems, if you experience any abnormal feeling symptoms such as palpitations (rapid heart rate), chest pain, etc. you should be evaluated.

Best wishes.