my baby has developed perioral hypopigmentation ,she s 7 months old now ,doctors told likely to be saliva allergy .1 month passed away still it's growing , wat could be reason and solution

A. hi was your baby drooling frequently? if so it can be allergy due to saliva or due to persistent wetness of the area around mouth . proper examination of the baby is needed in order to prescribe medication so better consult with the doctor personally