How Long After Neutering a Dog Is Testosterone Gone?

On average, a dog might need around six to eight weeks until testosterone is fully gone from his system after a neutering procedure. During those weeks, it’s normal to notice some aggressive behavior in your dog due to an imbalance in hormones.

After those eight weeks are over, you can expect changes in your furry friend’s behavior as his hormones settle down. You’ll start to notice signs like a calmer attitude, a reduced sex drive, and more.

9 Changes You Can Expect in Your Dog After Testosterone Leaves His System

Testosterone has a direct impact on many body functions in a grown dog. This is why a lot of pet parents choose to neuter their canine companions to improve their physical and mental health, and, most importantly, reduce aggression.

Here’s everything that the lack of testosterone will impact:

1. Activity Levels

Testosterone is linked to hyperactivity in dogs; by removing it, your dog should appear calmer than his usual self. Of course, this is a plus point for dog owners who have been suffering from destructive behavior and other things that a dog does when his energy levels are high.

This also helps reduce a dog’s tendency to bark or chase after people.

However, despite how heavenly this sounds, reduced activity is a double-edged knife. The more time your dog spends lying down, the easier it will be for him to become obese.

Therefore, it’s your responsibility to make sure your dog gets proper exercise regularly to reduce the chances of putting on more weight than is healthy.

2. Aggression Tendencies

There’s a solid connection between aggressive behavior in dogs and circulating testosterone in their bloodstream. So, by getting testosterone out of the equation, you can expect a less intense response from your pup toward things that used to trigger his aggression before.

Still, you should know that while neutering your dog can significantly reduce his aggression, it might not eliminate it.

This is because other factors come into play to cause aggression in dogs, such as:

• A response to fear
• An injury or illness that’s causing stress
• Prey drive
• Anxiety
• Past trauma

3. Fat Distribution and Muscle Mass

Testosterone has effects on the fat distribution in a human’s body, according to one study. Even though the same tests are yet to be performed on dogs, scholars believe that the same happens with canines.

This can explain why dogs are more likely to become obese sometime after being neutered. That’s another reason why providing adequate exercise for your pup is a must at this point.

In addition to that, the lack of testosterone influences the muscle mass of dogs because the hormone helps boost muscle strength.

4. Metabolic Rate

Another thing that changes with the drop of testosterone levels in a dog’s body is his metabolic rate. Metabolism decreases greatly with the lack of testosterone, which is another factor that might lead to obesity in neutered dogs.

The reason behind this is that getting rid of testosterone causes some hormonal imbalance in your pup’s system. In turn, this might cause the metabolism process to slow down, leading to a slower conversion of calories into energy.

Still, you can always keep your dog from gaining unwanted weight by encouraging him to work out and lowering his daily calorie intake.

5. Self-Confidence and Fearfulness

Unfortunately, circulating testosterone has been linked to self-confidence and reduced fearfulness in dogs. By getting rid of it, your pup might find it a bit harder to face troublesome situations without assistance.

For that reason, it’ll be your job to build your dog’s confidence once more and help him overcome stressful or fearful situations.

6. Sex Drive

Naturally, no testosterone in your dog’s body means significantly reduced sex drive. You can also expect instances of sexual humping to decrease.

Plus, a diminished sex drive will keep your pup from wandering in search of a mate. Therefore, trying to prevent him from going outdoors shouldn’t be much trouble anymore, boosting your little friend’s safety.

7. Separation Anxiety

Another thing you should be aware of after neutering your dog is that he’ll be more likely to suffer periods of separation anxiety.

This makes sense because of the increased chances of fearfulness that we’ve mentioned earlier.

To help your pup battle his anxiety, you can begin following a separation anxiety training routine. With determination and patience, your dog should learn to overcome this problem eventually.

8. Bone Density

Because testosterone directly affects bone mass and density, taking it out of the equation can help your dog stay away from bone diseases. Larger dogs can greatly benefit from neutering for this exact reason.

However, smaller dogs may suffer from the following diseases later in old age because of their decreased bone mass:

• Hip dysplasia
• Vertebral disc disease
• Osteoarthritis

This is why some dogs undergo testosterone therapy to give them a boost and make their bones stronger.

9. Body Hair Growth

Testosterone has an unmistakable impact on body hair growth in humans. That’s why boys notice a significant increase in body hair when they reach puberty; that’s when their testosterone levels are high. 

Even though we need further research on dogs to confirm this, scientists believe the same happens with our furry friends. So, if you notice a reduction in your dog’s body hair after testosterone is gone from his system, just know that it’s a side effect.

What reinforced this claim is that some scholars think that a dog’s inability to transform testosterone to DHT is what causes alopecia. For those who aren’t familiar with the condition, alopecia transfers to hair loss or lack of hair, and it goes for both humans and dogs.

Still, other factors come into play to cause this condition, so you can’t blame the lack of testosterone alone. This is why scientists aren’t 100% positive about the effects of testosterone removal on dog hair.

Here are other things that might cause alopecia in dogs:

• Aging
• Skin allergies
• Skin infections
• Genetics
• Lack of protein in a dog’s diet
• Scars or injuries
• Parasites
• Overgrooming

Paul S.

Paul has been creating content for the dog niche for many years. The information he shares comes his first hand experience growing up in dog lovers household and then owning multiple dog breeds of his own as an adult. Paul enjoys doing the hard research to collect, analyze and present our dogtemperament.com readers with the best answers to their questions.