Children with no hearing in 1 ear can be caused by the following reasons. First, it is caused by various infections. If a child is infected with rubella during fetal life, it can cause a hearing impairment in children and may even manifest as rubella syndrome. In addition to hearing impairment, children often have developmental malformations such as cleft lip and palate and congenital heart disease. There is no effective treatment for this condition, except for hearing, which can be improved with cochlear implants or hearing aids, and for children with deformities, which can be treated with plastic surgery in a timely manner. The second is caused by drug-related deafness. If children apply ototoxic antibiotics such as gentamicin or streptomycin, it can lead to damage to the ear hearing. In this case, the child can be given medication to nourish the ear nerve in the early stages.