Anyone with assistance, greatly appreciated- Mason has been wearing the same collar for over 10 months. Over the past 2 months, he's been getting lumps under his neck and has been scratching till the fur is gone. Vet prescribed oxy-dex. Not helping much. Only putting collar on to go outside. Then on to prednisone and Keflex. Clears up, but once meds stop, here the bumps come again. I've tried a choke collar chain (not for behavior, but to avoid materials on his neck) but they frequently break when he runs the yard on the leash. Has anyone been through this? If so, have you found a collar that is non-allergenic?