What Causes a Dog to Have Thick Mucus?

A dog often breathes through his mouth when he has a stopped up nose.
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A dog can have airborne allergies, nasal infections and blockages that cause thick mucus to flow from one or both nostrils. It is best to take your dog to his veterinarian for a diagnosis and treatment when he has any type of nasal discharge, especially if it is bloody.

Nasal Allergies

Canine airborne allergies occur when your pet's immune system recognizes an allergen as dangerous and reacts to it by having itchy, running eyes, sneezing and mucus flowing from the nose. Severe airborne allergens can cause nosebleeds and breathing problems.

Many items in your household can trigger allergic reactions such as pollen, mold, feathers, dust and dust mites, perfumes and cleaning products.

Taking your dog to your veterinarian may help to diagnose what triggers his allergic reactions. For example, canines who are allergic to dust may need their bedding cleaned more often; keeping windows closed prevents airborne allergens out of your home. If you dog is allergic to cleaning products and displays the signs after you clean, ask your vet about which floor and carpet cleaning products are better for your dog's allergies. Your veterinarian may prescribe allergy medications or give your dog allergy injections to alleviate his symptoms.

Nasal Blockages

If your dog's nasal discharge is only from one nostril, he most likely has a blockage. He may be sneezing, pawing at his nose and can get nosebleeds with a blockage. Common items are seeds or blades of grass that your friend inhales.

You can remove the item in your dog's nose with tweezers if it is close to the end of his nostril and you can see it clearly. If you are not comfortable doing this, take your pet to your veterinarian for removal of the foreign object. Your vet may need to sedate your dog to remove the object and may prescribe antibiotics for him to avoid an infection.

Nasal Infections

Canine nasal infections include a discharge of mucus or pus that may have a bad odor, include nosebleeds and a cough from choking on the postnasal drip.

Your veterinarian will determine the type of infection and a course of treatment. Bacterial infections usually require several weeks of antibiotics. Fungal infections are cured with oral anti-fungal drugs and sometimes a topical anti-fungal.

Bloody Nasal Discharge

In the event that your dog or puppy has pink mucus or bright red blood in his nasal discharge, take him to your veterinarian immediately. It can be a sign of allergies, a blockage or something more serious such as a tumor in his nasal passages or a dental abscess that needs immediate attention.