Please do not self-medication. Most cold and catarrh are viral infections that will be left to run its course."For catarrh, Keep your baby warm. Adequate hygiene around a baby is expedient. If nostrils are congested, u can buy saline drops to help relieve congestion or do steam inhalation (both of you will have to do it) If no improvement, kindly consult with a paediatrician for further assistance.