first order of business- flush the area with purified water and relocate the frog to a clean terrarium with no substrate as substrate can harbor pathogens leading to secondary infection. I’d strongly advise veterinary attention. A veterinarian can prescribe appropriate treatment whether it be topical antibiotics or otherwise. In the event you cannot get to an exotics vet a honey bath or a solution of purified water and Indian almond leaves can be used as a soak since both have antimicrobial properties. Neosporin without pain killer can be used topically but again I’d advise a vet trip.