K.M.
Noisy breathing is usually food allergies, and you can get help checking that out on docmccullen.com
With babies it is really important to find the underlying cause of any symptoms, as that is the way a body communicates a problem- look at the symptom and "pull the string" until you locate the reason, and then handle that- then the symptom will of course go away.
With any medication it is important to get the "fly sheet" that sheet that comes with the drug- if you don't have them you can go back to the pharmacy and get them- then read them- all the contraindications. Then you have the information to make decisions.
And really know what you know- you have observed what you have observed- put THAT into what you decide for your son.