We present a case of a sixty-year-old female who presented with sudden onset of painless loss of vision in one eye due to a perforated corneal ulcer, following three months of treatment with gefitinib, a selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor for metastatic adenocarcinoma of the lung with confirmed EGFR gene mutation. This evidence concerns the gene EGFR and corneal infection.