I first used a breakaway collar - but stopped that! One day Oscar was grooming his chest...his lower jaw got caught in the collar, and it did NOT break away! Thank GOD I was there, as he quickly started to panic.

I just got a collar from a pet store - adjustable, stretchy and reflective. I can adjust it so it is snug - but if he and his furbrother get into a fight, it stretches enough to pull right off and no one suffers!

Oscar's dosage was decided by the vet - 2 to 3 times a day. I did it twice a day for a long time; now it's once in the morning.

You might want to try that dosage schedule - or give your vet a call and see what s/he recommends.