First of all, you should isolate the sick pigeons and don't mix with other healthy pigeons to avoid infecting other pigeons. Pigeons with "one-eyed cold" have been infected by mouth and nose secretions and feces.
Then give 1/2 tablets (half tablets) of "Lijun Sha", which is available in pharmacies; Feed it once in the morning and evening, and treat the tearful eyes with erythromycin eye ointment for a week, and basically recover.
After you cure this "one-eyed cold", you can give it insect repellent in a day or two. Metronidazole 1/4 tablets (one tablet divided into four parts) can be given once in the morning and once in the evening for three days.
If there are conditions on the way, remember to drink "electrolyte water", which is what we often call normal saline, and give it to pigeons for free.