Hi my daughter is 10 and saw a NP 3 days ago. Dx: ruptured ear drum. Taking amoxicillin 500 bid. She came home with sore throat, headache, cough, and runny eyes (allergies) the NP suggest she take a Zyrtec 10 mg (this my rx, I am 45) question is..... Should I give her half or the whole 10 mg? Also, will this keep her up all night or make her drowsy? Thanks