Q&A on teenage dogs: Brain development, behavior, training strategies, and client guidance

Adolescence can be one of the most challenging and misunderstood stages of a dog’s development. During this period, many dogs display sudden behavior changes that can surprise pet owners and strain the human–animal bond, even when training has previously gone well. According to the American Animal Hospital Association, most dogs and cats relinquished to shelters, euthanized for behavioral problems, or abandoned are between 1 and 3 years old, when these animals are in their adolescent phase.¹

In this Q&A, adapted from an interview with dvm360 on his 2026 Veterinary Meeting & Expo session on teenage dogs, Christopher Pachel, DVM, DACVB, CABC (IAABC), breaks down the neurobiological and hormonal changes driving adolescent behavior in dogs. He explains why traditional training methods may fail during this stage, outlines an alternative approach better suited for teenage dogs, and discusses how veterinary teams can proactively guide client conversations before behavioral challenges become an issue. Understanding what’s happening in the teenage dog’s brain can help veterinary teams better support clients through this normal but often frustrating phase.

Editor’s note: This dvm360 Q&A has been lightly edited and consolidated from a verbal interview to better fit a written format while retaining the substance of the original conversation.

dvm360: What are some behavioral patterns common in adolescent dogs?

Pachel: There are so many adolescent dog patterns that closely mirror what we see in the adolescence of any species, including humans. Teenagers tend to be a bit impulsive and a little bit less well emotionally regulated. They tend to have "big feelings" in both directions—the positives are really positive, while the negatives are devastating—and we see some of that emotional volatility.

We also know that teenagers are experiencing the influence of some of those brain changes at a time when hormonal influences are also playing a factor for a lot of our dogs, cats, and humans, and so we may see behavior patterns associated with the onset of sexual maturity, such as urine marking, roaming behaviors, mounting, or other hormonally influenced challenges, all converging at a time when that dog looks like an adult, but from a neurobiological standpoint, they are anything but.

dvm360: You mentioned neurobiological changes. Could you dig deeper into the specific shifts occurring in the brain that drive these behaviors?

Pachel: Absolutely. To oversimplify things for the sake of demonstration, when we think about the brain and the way that it regulates emotions and behaviors, and that relationship between emotion and behavior, we often think about the prefrontal cortex—the area of the brain behind the forehead for both dogs and people. That region cognitively regulates arousal; it’s the executive center, heavily involved in decision-making and rational thought.

When we look at the way that that particular region of the brain operates in complement or contrast to the limbic system, that's where those emotional centers are really at the forefront of the influence they have on emotions and behavioral patterns, and there's this relationship that exists between them.

I often describe this to owners as a teeter-totter: if we're really emotional, it’s hard to access that rational decision-making piece of the brain, and vice versa. If we're very much in a ‘this is what I do’ versus ‘this is what I feel’ mode, sometimes it's hard to access or regulate some of the emotional responses. So, it's a relationship. Neither is better or worse. They're simply different parts of the brain working in complement.

What we know about the brains of teenagers is that the prefrontal cortex is not yet fully matured. In dogs, that often takes until they are between 2.5 and 3.5 years of age, depending on breed, size, and some other influences.

On the early side of the teenage months, we see a dramatic uptick in the activation of the limbic centers of the brain in a way that exaggerates emotionality and overrides the "thinking" part of the brain. This is actually supposed to happen—teenagers are supposed to be risky and "break the mold.” Even when we know better, our brains are kind of hijacking that process.

It’s not until we get closer to social maturity, usually around age 3, that those 2 brain regions come back together in a balanced convergence, providing fully developed executive function and a more modulated and mature emotional regulation system.

But, there's a lot of teenager to get through before we get to that point for dogs as well as for other species.

dvm360: How should the understanding of these shifts change how a professional designs a training plan for a teenage dog versus a puppy or an adult?

Pachel: I love this question. With puppies, we can often assume they are relatively naïve. They’re a "blank slate" (knowing that puppies aren't fully a blank slate, even as 6 and 8 week old youngsters) and we are laying learning experiences on top of that. By the time they hit 9 to 18 months, that animal is no longer naive; their learning history has accumulated.

If caregivers don't recognize the impact of the teenage brain, they often think, "We did our training, you know what to do." As the brain starts to go "offline" in that emotional direction, caregivers may resort to correction-based training to get the dog back in line.

While I really understand the frustration, what those teenagers need more than correction is consistency. They need consistency in expectations, training, exercise, enrichment, and daily routines. Every day doesn’t have to a mirror image of the next, but we need to consistently provide for the needs of those animals, knowing that they are changing during that teenage phase.

We need to acknowledge that even if a dog knows the rules, they are still going to break them sometimes because that’s what the dopamine in their brain is telling them to do. Management and continued education are key so that as the brain matures, they’re maturing in a consistent direction.

During adolescence—when the emotional system is dialed up and both positive and negative experiences are magnified—even a small correction may have a big impact. That impact may be positive in some cases, but it can also be negative and contribute to a traumatic experience that changes how the brain processes future stimuli.

So, for the average canine teenager, consistency of implementation is way more important than escalation of correction.

dvm360: How can veterinary teams begin having these "teenage" conversations with clients before behavioral issues reach a breaking point?

Pachel: I like to have them before they’re necessary. When I was in general practice, I would have these conversations as we were wrapping up the puppy vaccination or wellness series around the 4-to-6-month mark.

Often, there is a gap of up to a year before they’re “due” to come back in for a booster or some other diagnostic testing, and by then, they are 14 to 18 months old and fully in the teenager phase. At that point, we may now be trying to do repair work on that pet-owner relationship rather than being proactively in the driver’s seat to help guide and support our clients.

So, what I used to were 2 things. One of them was to say, “I would love to see your puppy back for a quick recheck somewhere around 8 months of age. That gives us an opportunity to make sure that physically they’re maturing the way they’re supposed to, that they’ve lost all their baby teeth the way they’re supposed to. Let’s take a look at those things.”

And secretly, what I was able to do in that 8-month appointment was say, “Hey, everything looks great”—hopefully it does—“and you may not know this already, but your dog is about to become a teenager. Things could go off the rails in a way that feels really frustrating or problematic. If that happens, even though I know your puppy is an angel and would probably never do these things I’m about to share with you, if they do, please know that a lot of this is actually normal, and it’s something that we can work with. I can help match you with a positive reinforcement trainer who can help guide you through that process.”

So for me, the answer to the question is proactive expectation setting: letting folks know that this is, in fact, something they’re likely to experience, normalizing it as part of that caregiver journey, and making sure they understand how I, my team, or the trainers in our community can be a viable resource to help them through it.

Reference

1. Age and behavior. American Animal Hospital Association. May 10, 2019. Accessed January 9, 2026. https://www.aaha.org/resources/2015-aaha-canine-and-feline-behavior-management-guidelines/age-and-behavior/?utm_source=chatgpt.com