My son 5 months 10 days having cold from 1 week .Using maxtra 0.4ml thrice a day from past 3 days and stopped 2 days again running nose started along with cough again started using maxtra from 3 days with same dosage.His running nose stopped but blocked with thick mucus .Using nasal drops but while baby breathing he is having mucus sounds from nose? should I need to continue maxtra or can I stop ?or should I need to increase the dosage plz suggest.