Inquiries on allergy and antihistamines

Patient: Hello and good day.I would like to ask if it is okay and safe to give my baby antihistamine everyday. I mentioned “everyday” because she always getallergy rashes everyday everytime she smells strong odor, eat something we are not aware is an allergen or other factors. We give her alnix 1ml. my baby is just 10 months old. Will it have a side effect?

Symptoms: Skin rashes, sneezing/coughing