Medicine allergies hard to predict

When in hospital recently the doctor started me on amiodarone for an irregular heartbeat called atrial fibrillation. I had a bad reaction that caused an awful rash over my whole body, including my eyelids, and it nearly drove me mad. I wasn't warned it could cause a rash. My GP has stopped that drug. Will the rash go away? Is there a substitute for amiodarone? - Sandy
Amiodarone is a powerful and complex medicine that suppresses fast or erratic heartbeats. Sometimes it's life-saving, allowing people with very serious heart conditions to lead nearly normal lives. But the price of that potency is a risk of adverse effects ranging from blue-grey skin discoloration, to vision problems, thyroid toxicity, liver disease and even lung scarring. Most of the serious side effects happen to people on high doses of amiodarone for long periods of time.
Your quick and widespread skin rash was most likely an allergic reaction. These are hard to warn against because they happen so unexpectedly. Once you've had a reaction, it's easy to guard against re-exposure, but the first time you break out it's usually a surprise for everyone involved, including your doctor. The medicine gets stopped, and the rash usually wanes over days (or weeks, in the case of amiodarone). It's annoying, but usually not dangerous.
Other treatments for atrial fibrillation need to be custom tailored to you. Your doctor has to consider the condition of your heart, the severity of your symptoms, and your risk of stroke, the most common serious complication of atrial fibrillation.
Alternatives to amiodarone include calcium channel blockers, beta-blockers and digitalis. For some people with atrial fibrillation, treating conditions like obesity or alcoholism will treat their arrhythmia. For others, treatment with electricity, called cardioversion, is an option. Your GP can match your treatment to fit your specific circumstances.
Don't be afraid to ask questions. Just keep in mind there's a lot about the human body that's unknown, and many outcomes we can't predict.
Gary Payinda MD is an emergency medicine consultant in Whangarei.

Have a science, health topic or question you'd like addressed? Email: drpayinda@gmail.com

(This column provides general information and is not a substitute for the medical advice of your personal doctor.)