A 6-month-old boy in Bangkok was brought to a hospital with a fever and cough. He was treated with favipiravir tablets, but 18 hours after starting, his mother noticed his normally dark brown eyes had turned bluish-purple. The discoloration was only in his corneas, and no other body parts were affected.
Doctors suspected favipiravir was the cause, as a similar case occurred in India in 2021. The antiviral is known to break down into fluorescent chemicals that collect in the cornea. This case is the first documented instance of a pediatric patient developing blue eyes from favipiravir.
After five days of treatment, the drug was discontinued. The child's eye color returned to normal within five days, and an ophthalmologist confirmed no lasting effects. The reason for the delayed recovery compared to the adult case is unknown, but factors like age and dosage may play a role.