Laryngitis in dogs – symptoms, breathing risks and treatment

Overview

Inflammation changes the voice and can narrow the airway

The larynx helps produce sound, and inflammation can change the bark. Coughing may be the main sign in mild inflammation. In more serious cases, swelling of the lining and underlying tissue narrows the laryngeal opening. Disease can involve respiratory infection or direct local irritation.

Laryngitis is distinguished from laryngeal paralysis, although both can cause similar signs. Inflammatory tissue changes can also resemble a tumour. Hoarseness or coughing alone therefore does not establish the diagnosis.

Inflammatory laryngeal masses are rare in dogs. One case series examined 5 dogs with bilateral movable inflammatory lesions. These represent a particular chronic inflammatory form, rather than the usual course of every case of laryngitis.

Causes

Irritants, injuries and respiratory infections

Inhaled dust, smoke and irritating gases can inflame the larynx. A foreign body can also cause local irritation. A breathing tube used during surgery can injure laryngeal tissue. Excessive barking is another possible cause of inflammation. Objects such as sticks can cause laryngeal injuries in dogs.

Laryngitis can occur with kennel cough. Kennel cough causes include several viruses and bacteria such as Bordetella and mycoplasmas. Distemper can also involve laryngitis. An infectious cause affects how exposure of other dogs is prevented.

Swelling and chronic tissue changes

An allergic reaction can also cause laryngeal swelling. In a short-muzzled or overweight dog, heavy panting and breathing effort can lead to inflammation and swelling.

Chronic inflammatory lesions can involve increased connective tissue, or fibrosis. They can also involve dilated lymph vessels and tissue oedema. A link between inflammation and eversion of the small laryngeal saccules has been proposed, but the precise mechanism is unknown.

Risk factors

A short muzzle, obesity and laryngeal paralysis predispose to laryngeal swelling associated with breathing effort. Overheating and excitement can trigger the situation in these dogs. Pugs are one short-muzzled breed.

Dogs in the movable inflammatory mass study had a median age of 11 years, ranging from 7–16 years. Their median weight was 3.50 kilograms, ranging from 2.85–5.38 kilograms. Three were Yorkshire Terriers. Two of these were a parent and offspring. Researchers considered inherited susceptibility possible, but its mechanism remained unclear. These cases cannot establish the breed's overall disease risk.

Typical symptoms

Coughing is often the first laryngitis sign you notice. It may initially be dry, short and loud, becoming wetter later. Possible observations at home include:

• A changed or hoarse bark.
• Coughing that looks painful.
• Noisier breathing than usual.
• Difficult or painful-looking swallowing.
• Standing with the head lowered and mouth open.
• Possible bad breath.

Pressure on the larynx, dusty air or swallowing rough food can trigger coughing. A cough triggered this way does not yet identify the inflammation's cause.

A healthy dog's usual breathing rate is around 12–30 breaths per minute. However, laryngeal narrowing can slow breathing while breathing effort increases. Clear respiratory effort is therefore a warning sign even without rapid breathing.

In the study of chronic movable inflammatory laryngeal masses, all dogs had mild, intermittent signs. Noisy, high-pitched breathing occurred in 4 dogs and voice change in 3. Snoring occurred in 3 and coughing in 2. Median sign duration before presentation was 30 days, ranging from 3 days to around 3 years.

Complications and consequences

Airway obstruction is the greatest danger

Laryngeal swelling can develop within hours. A narrowed airway can prevent adequate airflow. Oxygen deficiency can make mucous membranes bluish. Significant untreated narrowing can cause collapse.

Airway obstruction can impair your dog's temperature regulation in hot weather. Body temperature can rise considerably. Severe narrowing can also involve pulmonary oedema.

Painful swallowing and not eating can cause dehydration and deteriorating general condition. Death from suffocation is possible but rare; in dogs, another underlying problem such as laryngeal paralysis is often involved. This risk is assessed using breathing effort and underlying disease.

Diagnosis at the vet

Breathing assessment and laryngeal endoscopy

Your vet reviews the history of signs and examines breathing. Listening over the larynx helps localise abnormal respiratory noise. A high-pitched inspiratory sound can suggest narrowing of the airway outside the chest, such as the larynx. Partial large-airway obstruction may be audible without a stethoscope. Airway assessment and treatment proceed quickly if airflow is threatened. Oxygen saturation measurement can help but must not delay care.

Diagnosis is confirmed by direct laryngeal examination or endoscopy. In dogs, this generally requires anaesthesia or analgesia. During breathing tube placement, opening of the arytenoid cartilages on inhalation can be assessed, examining laryngeal function too. The whole mouth and throat are examined when time and circumstances allow. Assessment distinguishes diseases resembling inflammation, such as bilateral laryngeal paralysis, an abscess or pharyngeal injury. Other possibilities include an elongated soft palate, tracheal collapse and a foreign body.

Tissue changes can be sampled

When investigating a chronic inflammatory mass, an X-ray may show a soft tissue opacity within the larynx. The masses studied had a median largest diameter of 1.7 centimetres on X-rays, ranging from 1.3–2.0 centimetres. Fluoroscopy shows movement during breathing. Laryngeal ultrasound can also detect a movable mass. Histology of removed lesions in the case series confirmed chronic inflammation. On endoscopy, these masses were pink or reddish and stalked. Their mucosal surface was intact rather than ulcerated. They moved back and forth with breathing.

Normal blood tests do not exclude a local inflammatory mass: no significant abnormalities were found in 4 dogs in the 5-dog study. Pathogen testing is generally unnecessary in a single typical, uncomplicated kennel cough case. Severe disease or an outbreak spreading through a group may require more extensive sampling.

Treatment

Securing airflow comes first

Your vet selects treatment according to the cause and degree of airway narrowing. In an emergency, laryngeal obstruction can be bypassed with an opening into the trachea in the neck and a breathing tube. This aims to maintain breathing while the other problem is corrected. A tracheostomy may be needed particularly when the laryngeal problem prevents ordinary tube placement through the mouth. Oxygen is also part of airway emergency care.

A corticosteroid may reduce inflammatory swelling. If unsuitable, your vet may assess use of an NSAID. A diuretic may be used selectively for laryngeal oedema and any pulmonary oedema. Treatment may also need cough-suppressing medication. Your treating vet determines the medicines and their suitability.

Antimicrobials are used to treat bacterial infection. Ordinary uncomplicated kennel cough generally does not need an antimicrobial. Such kennel cough usually resolves untreated within 7–14 days. This interval concerns kennel cough, rather than airway obstruction or every form of laryngitis.

Removing a chronic mass and monitoring

In the movable inflammatory mass study, lesions were removed surgically in all dogs. Respiratory signs improved rapidly in every dog after surgery. No new signs suggesting a mass appeared during median follow-up of 13 months, ranging from 6–27 months.

Some dogs had follow-up X-rays after 7–10 days and others at 1 month. Images confirmed no visible masses. Postoperative endoscopy was not performed, so symptom-free recurrence could not be excluded. These results specifically concern the movable lesions removed.

Supporting recovery

Soft or liquid food may make swallowing easier. Pain relief helps the animal eat. Breathing humidified air may form part of measures to relieve signs. A clean environment and avoiding dust are supportive measures. Exercise and stress are avoided during treatment.

Prevention

Dust, smoke and irritating gases can cause local inflammation, so exposure is reduced. Identifying the stress or stimulation underlying excessive barking is also helpful. Avoiding heat and marked excitement is particularly relevant in a dog prone to airway narrowing.

Appropriate vaccination forms part of respiratory infection prevention. A dog vaccinated against kennel cough can still develop signs and shed pathogens. However, vaccinated dogs generally have less disease after exposure. Vaccination does not protect against local foreign body injury, for example.

Important for dog owners

Record voice changes and worsening breathing

Record when the bark changed and when your dog coughs. Tell the vet about possible smoke exposure, excessive barking, playing with sticks and recent anaesthesia. These details help investigate the underlying cause.

Monitor swallowing, appetite, breathing effort and general condition. If possible, take a short video of abnormal breathing sounds, provided filming does not delay seeking care. Do not press the larynx to test for a sign: pressure can trigger coughing.

Transport a dog with breathing difficulty calmly in a cool car. If your dog cannot stand, transport them lying on their breastbone with the chin supported and neck extended. You can phone the emergency vet beforehand so they can prepare for arrival. At discharge, establish which signs mean returning for care and how any postoperative check will be arranged.

Frequently asked questions

Can excessive barking cause laryngitis?

Yes. Excessive voice use is one possible cause of local laryngeal irritation and inflammation. However, respiratory infection, an inhaled irritant or a foreign body can cause similar signs. Examination investigates a changed bark, and difficulty breathing needs immediate help.

Is a hoarse bark always a sign of inflammation?

No. Laryngitis can change the bark. Similar signs can arise from laryngeal paralysis, an abscess or changes in surrounding tissues, for example. Your vet distinguishes these through tests; confirming laryngitis generally needs direct laryngeal examination or endoscopy.

Does a dog always need an antibiotic?

Not automatically. Bacterial infection can be treated with an antimicrobial. However, laryngitis can also result from direct irritation or excessive voice use. Most kennel cough cases are viral, so an antimicrobial is generally unnecessary. Your vet decides medication according to your dog's findings.

Can breathing slow as the situation worsens?

Yes. With laryngeal swelling, breathing rate may fall while the effort to obtain air increases. Counting breaths alone is therefore insufficient. Bluish gums, neck extension or collapse are respiratory warning signs requiring emergency help.

Is a laryngeal mass always cancer?

No. Laryngeal masses can be tumours or inflammatory lesions. In a small canine case series, histology of all removed masses was consistent with chronic inflammation. Appearance alone therefore does not establish a lesion's nature; diagnosis may require tissue examination.