# Flecainide-Induced Acute Respiratory Distress Syndrome: A Case Report

## TL;DR

A patient developed severe lung injury from flecainide after five years of use, which improved after stopping the drug and using steroids.

## Contribution

This is the first reported case of lung injury after flecainide re-initiation following a period of cessation.

## Key findings

- Flecainide-induced lung injury can occur after five years of therapy.
- Lung injury resolved after discontinuation and corticosteroid treatment.
- Re-initiation of flecainide after a break can lead to lung injury.

## Abstract

Flecainide is an antiarrhythmic drug that rarely causes lung injury. We present a case of flecainide-induced lung injury (FILI) that resulted in acute respiratory distress syndrome (ARDS) and resolved after flecainide discontinuation and corticosteroid treatment. FILI has been shown to occur days to two years after treatment initiation. Our presented case shows that FILI can occur after at least five years of therapy and is the first to show lung injury after a period of flecainide cessation and subsequent re-initiation. Clinical impacts may be large, as flecainide becomes more commonplace in medical pharmacopeia.