Hello , My Boy Is 3 Months Now And Catches

Hello , my boy is 3 months now and catches cold every morning and it's gets severe and does not feed until it subsides . We use saline drops and blow the mucus out with a blower. Is there any other remedy to treat cold completely ?? And can I give him wikoryl drops now that he is 3 months and 5days old . If yes what is the dosage ?? And also is it safe to give medicine to such a small baby . Worried pls advice