Chronic Hyperarousal

We have a 9 month old asian spitz type pup – I don’t want to be specific about his breed because the breed community is very small, and I’d like to be able to vent without worrying about judgement from a fellow owner or breeder. He’s our second dog of this breed – our first was the most incredible being I’ve ever had the honor of knowing. We also raised him from puppyhood, and he was intelligent, gentle, contemplative, and affectionate. We lost him to sudden illness last year. We have breed experience and a good understanding of what this breed needs in terms of mental and physical stimulation.

We adopted our current pup from his breeder at 9 weeks old, and we knew *immediately* that settling was going to be a struggle for him. I’ve had dogs my entire life – rescues, purebreds, puppies, seniors, labs, shepherds – and I’ve never encountered a dog who struggles to regulate the way our poor boy does. In the time between 9 weeks and 9 months, he’s never once voluntarily settled or napped for even five minutes. We’ve worked tirelessly on settle/place training, we’ve been doing various relaxation protocols since the first week he came home, we’ve tried varying how much/how little stimulation we provide, and none of it has translated to even a small measure of relaxation. He paces the house relentlessly if he’s not constantly engaged. He’s crate-trained and is quiet/calm in his crate, but even after months of regular, enforced naps, he still emerges from the crate and is almost immediately over-stimulated. Worth mentioning that we live in a very quiet and calm house – two adults, no kids or other animals. We live on a large wooded property, take him for daily hikes at nearby parks, and provide mental stimulation in the form of nose work, obedience training, puzzle toys, chews, and rip-up boxes. We’re both home with him all day, so outside of enforced naps, he spends very little time in a crate.

We consulted a veterinary behaviorist today, and she feels strongly that he has hypersensitivity-hyperarousal syndrome. She prescribed fluoxetine (Prozac) and says that dogs with similar anxiety-related behavior struggles typically respond very well to it. She said we could wait to start the medication until after he’s neutered – we hope to have him neutered in the next month, and even though I know it’s very unlikely, I’m hoping maybe it helps his behavior in some way. She did warn that waiting to medicate could potentially give his hyperarousal time to become even more habitual than it already is. While I know that objectively his condition isn’t necessarily a failure on our part (or his!), emotionally it feels a lot like failure.

Just wanting to vent and seek experience from anyone who has been through something similar. I’d love to hear from anyone with experience with fluoxetine, anyone whose dog was similar and just needed time to mature, anyone for whom neutering was a magic bullet (although I’ve read the research and know this is rare). I’ve never had to medicate a dog for behavioral issues – I’ve never even had to seek professional help for behavior issues. I want him to be happy and well, and we’re willing to do whatever it takes to get him there. Appreciate any help.