I'm happy that you have asked me to assist you with your child and hope that you can benefit from my many years of helping parents like you. Unfortunately there are no safe medications for children that age but here are some tips to help him be more comfortable: use the suction bulb to help keep his nose clear since babies that age still prefer to breathe through their noses, not their mouths, use saline nose drops (NaSal, Baby Noses, etc.) to help loosen the mucous in his nose before suctioning, keep his crib propped up on the head end to promote drainage, or let him sleep in his car seat, use a humidifier near him while sleeping to keep the secretions thinner with the dry air we experience during the winter with our heat on all night.
Medications we use in older kids are just too strong for infants and that is why they are not on the shelves at stores and pharmacies any longer.
As long as he is able to eat, is sleeping ok, and has no fever then you can just do the things I listed above. Should his condition change (refusing feeds, fever, etc.) then he needs to be rechecked by his doctor.
Thanks for the help. Maybe we can sleep better.