Hives

Hi my 7 year old has had really bad full body hives for around 2 weeks that got that bad her face swelled an she got treated for possible shock in ambulance just to be on safe side ended up in hospital 2 days they just still saying viral seen 3 docs before that also saying viral but they said looks like alergy at first anyway she got put onto steroids for 5 days they settled an just showed on legs little bit here an there but now 3rd week there back now steroid have finnished more like they starting up again but no where no where near as bad as they was just yet less raised an not as many as before just yet but im worried they going get worse has anyone else been through this did they eventually go away was it viral been on piroton 3 weeks now aswel an necusse they was still bad in hospital avtuslly worse they saying not food related