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I wouldn't. It is likely too strong, and you will need it in ointment form. You can get an ointment for your boy without a prescription called Terramycin. Some pet stores carry it, (call first to see) or your vet may stock it as well, and be able to sell it to you without seeing your boy. Clean the eye with a warm wet papertowel without tugging to help keep it from sticking shut. You should see an improvement with the ointment within 2 to 3 days, but continue for about 10 to make sure the infection is completely gone. If no improvement he may need a stronger prescription strength.
Hope he is better real soon!