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Dog Drooling Thick Saliva [Why & What To Do]

Thick Saliva. A slobbery dog. It’s pretty gross, right? But aside from it being a little nauseating and even inconvenient, it does naturally make us wonder and even worry why our dogs are drooling such thick saliva. Is it a cause for concern? Is there anything you now need to do? Well, here is everything you are going to want to know.

So, why is your dog drooling thick saliva? Your dog may be drooling thick saliva because he’s dehydrated or suffering from heat stroke. Other times it could be your dog is experiencing side effects from medication. Some dogs may even have dry mouths or are experiencing an allergy.

As you can see, something is up.

But how do you identify which one it is?

Well aside from checking in with your vet, I thought I’d walk you through each potential cause in further detail.

From there, we will be looking at the most appropriate response in each context. So, stick around.

Besides, you may be able to support your dog pretty much instantly and even ease some discomfort if you do.

Why Is My Dog Drooling Thick Saliva?

Thick saliva can be caused by dehydration, heat stroke, or as a side effect of medication. His saliva could also be thick because of an allergy or as the result of a dry mouth. More rarely, thick saliva can come as a result of rabies.

Your Dog Is Dehydrated

Causes Of Dehydration

The most common cause of thick saliva in dogs is dehydration.

When your dog is dehydrated, his body is losing fluids at a faster rate than he can replace them. The body loses water and other essentials for health, such as electrolytes.

Dehydration can be caused by various things, such as:

  • Severe diarrhea
  • Vomiting
  • Gastroenteritis
  • Canine parvovirus

Several infectious diseases can cause your dog’s stools to turn liquid or for him to vomit up fluids.

If you see any vomiting or diarrhea, it’s always worth a quick phone call to your vet to determine whether your dog needs to go in for checking.

Sometimes dogs get dehydrated because they aren’t drinking enough water. Causes for this include:

  • A high fever (so your dog doesn’t want to drink)
  • Lethargy (he might be too tired – lethargy is a common side effect of many serious illnesses and is usually a cause for concern)
  • Inflammation (your dog might find drinking painful)
  • A foreign object is stuck in his throat (potentially blocking his airway. An obstruction requires immediate attention)

How To Tell Whether Your Dog Is Dehydrated

You can do the following test to see if your dog is dehydrated:

  1. At your dog’s withers, take a fold of skin and carefully stretch it.
  2. Release the skin and see if it returns to its original position immediately.
  3. If the skin doesn’t snap back right away, your dog is almost certainly dehydrated.

Other symptoms of dehydration in dogs include:

  • Sunken eyes
  • Gum residue
  • Dry mouth
  • Dry spittle around his lips

Your Dog Has Heat Stroke

Heat stroke can cause thick saliva and is considered to be an emergency.

If your dog has been in an environment that’s too hot for too long (e.g., a warm car or a hot house), his body temperature will rise, and he’ll have trouble cooling down.

Even exercise in hot weather can cause heat stroke if your dog isn’t able to cool down sufficiently.

Brachycephalic dogs such as pugs tend to suffer more from problems such as heat stroke because of their flattened noses and shortened palates.

If your dog maintains a too-high temperature for too long, he will die.

In addition to thick saliva, symptoms of heat stroke include:

  • Vividly dark mucus
  • Gasping for air
  • Discolored tongue
  • Trouble breathing
  • Fever
  • Diarrhea with blood
  • Vomiting
  • Shock
  • Collapse

Your Dog Has Side Effects Of Medication

Sometimes your dog can have an adverse reaction to a particular medication.

If you think this is the case, take your dog to the vet quickly to prevent any further complications.

In severe cases, your dog may need his stomach pumped as well as other treatments. In less serious cases, a change in medication can be enough.

One medication that can cause dry mouth is Claritin, an antihistamine drug to treat allergies. Other veterinary medicines that can cause thick saliva include:

  • Diuretics
  • Other antihistamines
  • Decongestants
  • Sedatives
  • Atropine

Some medical treatments, such as radiotherapy, can dry out your dog’s mouth, too, and thicken his saliva.

Your Dog Has Dry Mouth

Dry mouth can cause not only thick saliva but a cracked tongue. You’ll want to get to the vet as soon as possible.

Dry mouth can cause other problems for your dog, such as:

  • Dental diseases
  • Dry or cracked oral mucus membranes
  • Bad breath
  • Cavities
  • Trouble swallowing or chewing food

Your Dog Has an Allergy

One of the symptoms of an allergic reaction can be thick saliva.

For instance, dogs who are allergic to mushrooms can react with thick saliva if they bite, chew, or carry mushrooms in their mouths.

Your dog’s defenses will think the mushroom is something deadly and will produce thick, excess saliva in an attempt to prevent any toxic substances from entering the body.


Though much less common now than it was, rabies can still be a concern, depending on where you live and whether your dog has been vaccinated.

Rabies is transmitted when one infected animal bites another.

Rabies affects many animals besides dogs and can be found worldwide.

Nevertheless, there are some countries which have been free of rabies for quite some time:

  • Iceland
  • Ireland
  • Japan
  • New Zealand
  • Australia
  • Antarctica
  • Pacific Islands (some)
  • Parts of Scandanavia

The incubation period for rabies can vary from ten days to a year or more.

In dogs, the usual incubation period is from two weeks to four months. The speed at which rabies develops depends upon:

  • How severe the bite is
  • Where the bite is (the closer it is to the brain and spinal cord, the faster the virus reaches nervous tissue)
  • How much of the virus was injected with the bite

In addition to thick saliva, other signs of rabies include:

  • A change in temperament (from quiet to agitated or from active to shy or nervous)
  • Symptoms of a depraved appetite (similar to pica where dogs will eat anything)
  • Progressive paralysis (sometimes this can seem as if your dog has something stuck in his throat)
  • Coma and death

Rabies is a deadly illness with no cure.

However, sometimes early use of the anti-rabies serum can interrupt the progression of the disease if caught early enough and not too much venom has been absorbed.

What To Do About Your Dog Drooling Thick Saliva

What to do about your dog drooling thick saliva depends on the cause. Some conditions are more urgent than others (see below).

If Your Dog Is Dehydrated

What To Do

You will need to act quickly if your dog is dehydrated because without treatment he could go into shock and die.

Get your dog to the vet as soon as possible for prompt rehydration.

You may wish to give your dog an electrolyte solution to replace lost fluids and minerals.

Speak to your vet to determine if you can administer fluids on your own, or if an intravenous treatment is required.

Your vet will administer a fluid treatment (either oral or intravenous, depending on the severity of the dehydration)

How To Prevent Dehydration

Make sure your dog always has access to plenty of clear, clean drinking water to prevent dehydration.

Remember your dog will need to replenish his fluids after exercise or in warm weather.

As a general rule, dogs require one fluid ounce of water per pound of body weight per day.

Check with your vet for advice if you are unsure how much water your dog needs daily.

Or use my calculator below.

How Much Water Should A Dog Drink Calculator

If Your Dog Has Heat Stroke

If your dog has heat stroke, you’ll need to get your dog to the vet urgently, as any delay could be fatal.

Make sure you keep your dog as cool as possible on the way to the vet.

Your vet will give your dog intravenous fluid therapy to replace lost liquids and minerals. They will also monitor your dog closely to make sure there are no complications, such as:

  • Blood pressure changes
  • Clotting
  • Kidney failure

If Your Dog Has Dry Mouth

If your dog has dry mouth, urgent action is needed, as your dog may not be able to drink on his own.

Your vet may administer fluid therapy to your dog. If the case isn’t too severe, your dog may only need an oral fluid solution.

However, if your dog has other complications or is vomiting, your vet may need to introduce fluids intravenously.

There are simple things you can do to make sure your dog’s saliva stays healthy to prevent future problems, such as:

  • Brushing your dog’s teeth regularly
  • Using mouth cleansers (these reduce mouth bacteria as well as plaque)
  • Choosing the appropriate food for your dog

If Your Dog Reacts Adversely To Medication

If you suspect your dog is reacting negatively to medication, take him to the vet as soon as possible.

It’s essential to make any changes in medication quickly to avoid further problems for your dog.

Note: Before changing any medication for your dog, check with your vet. There are some over-the-counter medicines that are toxic to dogs.

If You Suspect Your Dog Has Rabies

Although it is unlikely your dog has rabies, it’s worth knowing what to do just in case.

One of the earliest symptoms of rabies is a change in your dog’s temperament.

If you notice your dog’s temperament has changed and you suspect he may have come into contact with an infected animal, get him to the vet immediately.


So there you have it.

Six potential causes behind your dog’s thick saliva.

One thing I’d say is to watch your dog closely.

See if the thick saliva is accompanied by any other symptoms.

If in doubt, be absolutely sure to contact your vet. Particularly if it persists.

Nevertheless, you may find with some hydration; it goes away.

So over to you.

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