Sinarest and cetirizine should not be given together as both of them contain same type of drug, antihistamine.
Sinarest has chlorpheneramine maleate which causes more sedation than cetirizine. In addition it has a decongestant for running nose
By wheeze do you mean noisy breathing? Because if a doctor gets wheeze on examination of the chest, he or she will prescribe a bronchodilator
like Salbutamol(Albuterol). If what she has is just an allergic cough
, Cetirizine will do.
Hope you find my answer useful.