Hi I understand your concern. Yes, your information about cetrizine is not wrong. But first thing your wife is 3 months pregnant. Harm ful medicine is to be avoided in first 3 months of pregnancy-as this is the time when basic develoment is going on, - If your wife does not get relief with home remedies within 5 days/ she has fever, yellow sputum or nasal discharge- she needs treatment. A short course of anti allergic drugs can be given safely & will be preferred over the risk of getting , cough,fever or complication like pneumonia - So please don t worry, consult your doctor & get her treatment as per his advice,Timly treatment needs lesser drug & lesser chance of side effect.. Thanks