Give him a great big shot of Liquamycin LA.  The penicillin in the eyelid works too, but you need a good headgate.  Inject it up under the top lid, and it seeps out the hole over the next few days.  Patches are a good idea too.

There's a vaccine for it, and believe it or not, giving it to an animal who already has pinkeye will help clean it up.