I have experience with the head collar variety.
I highly recommend this as a training tool. It's important to directly supervise the dog while it has it on at all times, of course, otherwise they might end up hurting themselves.
I also noticed that most dogs will take awhile to adjust to the gentle leader, so using positive reinforcement (treats) to get them to *want* to wear it is helpful. As well as starting with small amounts of time that the dog uses it and then working up to longer periods of time. Overall, I can say I've seen big results in very little time with this.
A nice feature with gentle leader is that they will replace a *damaged* (code for chewed/destroyed) collar for only a few dollars. Nice to know when they cost $25 or so.
Have you asked your vet what s/he thinks would work best for your dog? |