Dog’s Breath Smells Metallic (or Like Iron & Blood)

Dog’s Breath Smells Metallic

Dogs have a range of smells, most of which you can usually figure out. But if you’ve ever noticed that your dog smells like metal, particularly their breath, it can throw up all sorts of questions… below I will explain why your dog’s breath smells like metal and when to worry.

But, before I go on, please don’t assume that the metal or iron like smell from your dog’s mouth is blood. Often, we associate blood with a metallic taste, so you might think your dog’s breath smells like blood… but that’s not what this is. Here’s the short answer first, then more detail lower down the page.

Why does my dog’s breath smell like metal? Dogs’ breath can smell metallic for several reasons. The most common is due to their anal glands, and the most serious reason is kidney failure.  

The metallic dog breath (like ammonia) can be caused by a build-up of toxins not being filtered by kidneys.

But before you freak out, this isn’t the only reason why a dog’s breath smells metallic, there are other more benign reasons too, all of which I will explain below… with the most common being a smell transferred to their mouth from their anal glands.

If you are worried though, please consult with your vet.

Why does my dog’s breath smell like metal?

Metallic dog breath has many causes so it might not be necessarily a serious health problem such as kidney problems. Here’s are alternatives reasons as to why your dog’s breath smells like iron or metal.

1. The metal smell is due to diet high in protein and meats

Some dogs will have metallic smelling breath due to their diet. You might also think your dog’s breath smells like blood depending on your own sense of smell.

If your dog eats a lot of protein and meats, the protein can come back up into their mouth resulting in that smell. You might consider mixing the diet up a bit to not be to protein concentrated.

Handy Hint: If you do get a diagnosis that the metallic smelling breath is kidney related, here’s what vets recommend dogs with this condition need to eat.

2. The metallic smell is blood

Perhaps it is a smell of blood in your dog’s mouth. Have a check and see what they have been chewing on – toys and rawhide can cause mouth lacerations and bleeding.

The places most susceptible to wounds are the roof of the mouth and on their gums.

3. The metal smell is due to anal glands

One of the more disgusting reasons for your dog’s breath smelling like metal is their anal glands. This might sound strange, but it’s quite simple… they lick their own behinds.

Both male and female dog will get metallic smelling breath, like iron, where they have licked their but after the anal glands have leaked.

This isn’t the most pleasant of topics, but it needs discussing.

Anal glands are a pair of sacs positioned either side of your dog’s anus. They contain a smelly fluid that is oily to the touch. It will occasionally secrete out of the glands with the smell being compared to fish, ammonia, blood, iron, or metal.

This isn’t a problem, it’s entirely natural.

The smell that comes from the anal glands is your dog’s own personal trademark. When he defecates, his poop will have this unique smell, it’s a calling card and lets dogs know who’s been where.

Anal glands are how a dog marks territory and how dogs identify each other.

This is also what is happening when dogs greet each other and smell each other’s buts. It’s all about the anal gland smell.

So, how does this translate into your dog’s breath smelling like metal?

Well, if your dog is biting or licking at their anal region, that smell of the anal glands will then transfer to their breath.

Handy Hint: Sometimes vets will offer to express a dog’s anal glands if they become impacted and sore. Here’s my take on whether this is necessary.

But this could mean that your dog has anal sac disease is the smell is frequent and very strong of metal.

If you do have any concerns, talk to your vet.

Anal glands can become impacted and leak due to the following reasons:

Possible causes of impacted anal glands

Several risk factors can cause a dog to suffer from impacted anal glands. The UK Kennel Club say this:

“Anal glands can fill for several reasons; most commonly when there hasn’t been enough pressure to empty the glands, such as, after a few days of diarrhoea. Whenever they haven’t emptied properly, there’s a chance that glands can become blocked, impacted, and swollen. If they’re impacted for too long, they can build up nasty bacteria, causing pain, increased swelling and sometimes even abscesses and fever.”

4. The metal smell is due to a dental problem

Another reason for dogs having metallic smelling breath can be a dental issue. This can include rotting gums and teeth or an infection. This is most common in older dogs.

It could also possibly be an ulcer in the mouth, so see if your dog will let you check.

dog breath smells like iron or metal
Dogs can also smell like metal after rolling around at the park.

Why does my dog’s urine smell like metal?

At the top of the article, I explained how metallic smelling breath in a dog can be due to them having a kidney problem. Hopefully this won’t be the case with your dog, but if you also smell metal around their urine, you should investigate it further.

This can affect both male and female dog urine smelling like metal or iron.

Incidentally, another sign of kidney disease is an ammonia-smelling breath.

Other reasons why a dog smells like metal (not the breath)

It might not just be your dog’s breath that smells metallic. The odor could be coming from their fur or elsewhere. Here are the other reasons why your dog smells like metal:

  • Dog has rolled in something, or anal gland secretions are on the fur.
  • Blood from an injury on their body somewhere.


In my experience, the most common reason for dog breath smelling like metal will be from where they have licked their backsides and transferred odors from the anal glands to their mouth.

While this is the most common in both male and females, your dog’s metallic smell is not always the fault of the anal glands. Read on to find out why else your dog could be smelling like iron or metal.

But it might not be.

The next time you smell metal, iron, or blood on your dog’s breath, give them the quick once over to check for injuries not just inside the mouth, but also around their body.

If there’s nothing visible, check for a foul smell towards their rear.

If it’s not the anal glands causing the metallic breath smell, perhaps it’s their diet.

Either way, if it does persist, pleased consult a vet for a professional opinion. 

You might also like… 

Marc Aaron

I am one of Claude the French Bulldog's human parents. I write about all the things we've learned about owning a Frenchie, the adventures we have, and any advice and tips I've picked up along the way. Read more about Marc Aaron.

Recent Posts