How Long After Neutering Does a Dog’s Behavior Change?

Dr. Joe Alcorn, M.S., D.V.M.

Dr. Joe Alcorn is founder of Care Animal Hospital in Temecula, California. He has a Bachelor of Science in Biology and Doctor of Veterinary Medicine from Colorado State University. He is a member of the American Veterinary Medical Association and his advice has been featured in large publications like Bustle and Martha Steward.

Home » Blog » How Long After Neutering Does a Dog’s Behavior Change?

The population of dogs in the whole world is continuously increasing. Some of them end up in a shelter, and some might end up being euthanized. So one solution that dog owners and vets suggest is neutering your dog. Though, how long after neutering does a pet’s behavior change?

How Long After Neutering Does a Dog’s Behavior Change?

After the neutering procedure, the behavior shift in dogs can happen after 6 weeks. This may vary depending on the dog’s production of testosterone, the male hormone. Sometimes, neutered dogs may still show behaviors of an intact dog and attempt to mount a female dog in heat. 

Eventually, the production of this hormone will diminish and your dog will have noticeable changes. Their behavior will change and their activity level may also get reduced. No need to worry, these changes don’t mean that your dog is sick. It only implies that the surgery is effective.

Neutering dogs doesn’t just help in reducing the number of the dog population. This procedure can also prevent some cancers that are prominent in dogs that are not castrated. Getting your dog sterilized can also be an indication of being a responsible owner.

A close up shot a young brown dog

Behavioral Changes in Your Dog After Neutering

After the neutering, there are several things that you need to observe and the changes that you will notice in your male dog. Be reminded that not all dogs will experience all these. Some dogs may even experience very minimal change, too.

  • They will be less likely to mark their territory by splashing their urine. They will be more disciplined when it comes to their potty area.
  • They will show less aggressive behavior than before. 
  • Your male neutered dog will no longer try to escape to find a mate. 
  • Appetite may increase in some dogs. This is the reason why they may gain more weight aside from just sleeping all day long. Therefore, it makes exercise more necessary.
  • Roaming is also reduced and they will either stay with you on the couch or stay in their bed to sleep.
  • Barking is also reduced in some dogs.

You should know that neutering your male dog will not resolve any previous behavioral problems. Castrating your dog can only diminish its sexual drive. Those behavioral changes vary from one dog to another. It is still better to talk to me if you think there’s something unusual with your pet.

Will Male Dogs Act Different After Being Neutered?

Yes, while neutering brings several health benefits (such as less risk for prostate disease) some male dogs may experience changes in their behavior after being sterilized. For instance, some neutered male dogs become nicer and more friendly to humans. Also, recently neutered dogs might start sleeping more than before.

However, these are the most common changes; this surgery can also lead to other shifts that might concern dog owners. After all, some male dogs can even experience depression, anxiety, and other changes.

Depression After Neutering

After neutering, some male dogs may experience anxiety or depression. This might be caused by shifts in hormone levels after surgery. The most common symptoms of depression are decreased activity, appetite loss, and social withdrawal.

Clinginess and Fearfulness After Neutering

Male dogs may exhibit confusion or clinginess immediately after neutering. They may feel lost and uncertain of their surroundings, and they might need extra care and comfort from their owners. The male dog’s behavior might be like this for a couple of days until he goes back to normal.

Also, some male dogs may lose their confidence and authority, which can cause them to show fearful behavior around other male dogs. This change in the dog’s attitude might be one of the biggest changes, after all, the male dog’s attitude is often very territorial around other dogs; this can change after neutering.

Aggressiveness After Neutering

In rare cases, a neutered male dog might become aggressive right after being sterilized. This strange behavior happens because of the changes in their hormone levels, or simply by the discomfort after surgery. Regardless of the reason, you should monitor your pet’s behavior and contact me for help if you notice any concerning behaviors. 

If the recovery process is done and your neutered dog continues to be aggressive, he might need to be trained by a professional. However, remember that this is not one of the most common behavioral changes, in fact, this doesn’t happen very often.

Nausea and Unease After Neutering

After neutering, some male dogs experience nausea or unease. This could be because of the anesthesia used or because of discomfort from the surgical site. Because of this, I always give instructions for post-operative care, this way I help to minimize any discomfort your male dog may experience.

Other Changes to Expect After Neutering

As I mentioned before, you can expect other changes such as a decrease in their energy levels, more or less appetite, and a different sleep pattern. This depends a lot on your dog’s system and breed. Some may become more active and eat more, while others might become less active, and sleep more.

How to Help Your Male Dog After Neutering

Although this is a very safe process, the dog needs post-operative care. This is why, after neutering, I provide you with instructions for proper care. Some of them are to limit their activity, such as walking post neutering, and to keep their surgical site clean and dry. 

Also, sometimes I provide pain medication, therefore, you will need to administer it to them. Do not hesitate to seek assistance and guidance if you notice any concerning changes in your pet’s behavior or health.

Why You Should Sterilize Your Dog

Dogs should be neutered to prevent unplanned litter of puppies. We know that they are really cute and it’s fun to watch them grow. However, having a pregnant dog in the house also means having big responsibilities and an additional budget for them. 

A dog resting on a bed after neutering procedure

Once the breed is born, you should take good care of them before planning to rehome them. As a responsible breeder, the puppies should also be trained and socialized and they should have primary vaccinations as well. These things can eat both your time and money.

Aside from controlling the population, there are other health benefits your dog can experience after neutering

  • Neutering your male dog can highly reduce prostate problems, such as cancer or tumor.
  • They are also less likely to have testicular cancer because both testicles will be removed. 
  • Neutered male dogs have a reduced chance of acquiring perianal tumors found around the anus and testes.

When it comes to the age when to sterilizing your male dog, your pet’s condition and maturity also matter. Not all canines mature and develop at the same rate. Generally, you should neuter your dog from 6 months to 2 years old. My recommendation is an important consideration.

Neutering your male dog too early or too late can affect their health. They can develop cancer and other kinds of diseases and infections. They also get obese and diabetic. Behavioral problems may also arise because of this.

How to Monitor Neuter Surgery Incision

To prevent the incision from getting infected or getting stitched again, it is good to keep an eye on your dog. If you see that your male dog keeps licking or scratching the incision, have him wear an e-collar to prevent him from reaching the wound. 

Clean the incision regularly to prevent the overgrowth of germs and viruses. Change the bandage at least once a day. Once the incision is almost dry, do not cover it anymore with a bandage or gauze to allow the wound to dry and heal completely.

Signs that your dog’s incision is infected, you may see frequent red spots or redness around the site. A discharge may also be observed. It can be white, yellowish, or blood-red. An incision can be infected if it produces a foul smell. Swelling or bulging is also unusual. Consult me if any of these happens to your male dog.


After neutering your pet, its behavioral shifts may begin 6 weeks after the surgery. It includes reduced aggression, humping on female canines and people, escaping, and roaming around. Male dogs can have different behavioral changes depending on their breed, age, and maturity.