Adolescent Dog Behavior Changes: Regression, Testing and Hormones

By Tailwisp Editorial TeamUpdated October 17, 20263 min read

The teenage phase can test even patient owners.

When adolescence happens

Dogs reach sexual maturity around six to twelve months, and social maturity later, often between one and three years. Large breeds mature later than small breeds. Adolescence is a gradual period of change.

Typical changes

• Ignoring known cues, known as selective hearing.
• More energy and zoomies. See why do dogs get the zoomies
• Chewing and destruction. See why do dogs chew everything
• Testing boundaries.
• New fears: fear periods may occur.
• Reactivity toward dogs or people.
• Hormonal behaviors, such as marking or mounting.
• Increased roaming or escape attempts.

Why it happens

Brain development, hormones and independence all play roles. Dogs are learning to be adults, and their impulse control is still developing.

Staying consistent

1. Keep rules and routines.
2. Revisit basics: sit, down, recall.
3. Use high-value rewards.
4. Train in short, fun sessions.
5. Increase exercise and enrichment.
6. Supervise and manage.

Chewing

Provide safe chews. Teething may be over, but chewing remains. See puppy teething timeline.

Recall

Adolescent dogs often lose recall. Use long lines and avoid practicing failure off-leash.

Fear periods

If your dog suddenly fears something, stay calm, give space and use rewards. Do not force. Fear phases usually pass.

Social behavior

Dogs may become less tolerant of puppy behavior, or more reactive. Choose playmates carefully. See is my dog's play too rough.

Spay and neuter timing

Discuss timing with your vet, considering breed, size and health. Behavior effects vary. See behavior changes after spay or neuter.

Avoid harsh methods

Punishment can damage trust and worsen fear. Focus on reward-based training.

When to seek help

If aggression, intense fear or severe destruction appears, consult your vet and a behaviorist. See when to see a dog behaviorist.

Common mistakes

• Giving up training.
• Punishing.
• Under-exercising.
• Trusting off-leash too soon.

Troubleshooting

• My dog forgot recall: use a long line.
• My dog is destructive: manage, exercise and supervise.
• My dog is afraid of new things: go slowly.

A simple plan

1. Stay consistent.
2. Exercise and enrich.
3. Manage risks.
4. Be patient.

Real-life examples

A lab ignores cues at eight months and improves with high-value treats. A shepherd develops a fear of mailboxes and recovers with gentle exposure. A terrier chews furniture and does well with chews and supervision. The phase passes.

Looking ahead

With steady training and kindness, adolescent dogs grow into steady adults. Celebrate small wins and keep a sense of humor.

Keeping your sense of humor

Adolescent dogs can be exasperating, but they are also exuberant, curious and funny. Celebrate small successes, and remember that they are still learning. A short break from a difficult cue, followed by an easy win, helps both of you stay positive.

Training refreshers

Return to the basics with high rewards, a calm environment and short sessions. Practice each cue in new places, adding distractions slowly. Many dogs bounce back quickly when trainers reduce pressure and increase fun.

Exercise that helps

Mix physical exercise with mental games. Sniff walks, tug, fetch and training sessions all help. A tired adolescent is a good adolescent, but avoid overexercising growing joints, especially in large breeds. Ask your vet what suits your dog.

Working with a trainer

A good trainer can help you through adolescence with group classes, private sessions or online support. Ask for reward-based methods and realistic goals. Having a coach reduces stress, and keeps you consistent when your dog is testing limits.

The takeaway

Adolescence is a challenging phase. Stay consistent, patient and kind.