Various medications are administered to treat Coronavirus Disease 2019 (COVID-19) infection and prevent its complications. Some medicines have complications and long-term effects, which may mimic other conditions, making precise diagnosis difficult. This report aims to bring to light one such complication, medication-related osteonecrosis of the jaw (MRONJ), secondary to a commonly prescribed medication for preventing lung fibrosis post-COVID-19 infection.

A 33-year-old male reported to our department with the typical clinical and radiological features of Mucormycosis of the upper jaw post-COVID-19 infection. However, on detailed evaluation of his history (controlled diabetic and short duration of steroid therapy) and review of the mycology staining, bacteriology, culture, and histopathological reports, we came to a negative diagnosis for Mucormycosis. The patient was, however, on treatment for the prevention of lung fibrosis with Nintedanib (tyrosine kinase inhibitor) 150 mg twice a day for one month.

In the absence of predisposing factors and negative laboratory findings for mucormycosis, we arrived at a diagnosis of MRONJ, attributable to Nintedanib therapy given to prevent lung fibrosis post-COVID-19 infection.

The use of Nintedanib has recently increased due to the high incidence of lung fibrosis post-COVID-19 infection. However, Nintedanib should be considered a causative agent for osteonecrosis of the jaw in the absence of other obvious predisposing factors. Therefore, Nintedanib must be administered after a thorough consideration of risk factors.