A dog’s tongue can be an indicator of overall health, from hydration level to dental concerns. However, regarding changes of color in a dog’s tongue, turning it blue is one of the most critical concerns for almost any pet owner. Although certain breeds such as the Chow Chow and the Shar-Pei have naturally blue or black tongues, a sudden blue tongue in other dogs is usually a sign of a serious medical condition called cyanosis. The article provides information on causes—such as respiratory problems, heart conditions, and toxin exposure—symptoms, diagnosis, treatment options, and preventive measures for blue tongue in dogs. We’ll discuss which breeds have naturally blue-colored tongues.
While a blue tongue can be a cause for concern in many dog breeds, it’s perfectly normal for some. Some breeds do have naturally blue-black or bluish-purple-colored tongues because of their heavy pigmentation. This pigmentation is just an abundance of melanin, the same pigment that dictates skin and hair color in humans and animals. It is genetic and passed down through generations. So, if you have one of these breeds, a blue tongue shouldn’t be a cause for alarm.
Probably the Chow Chow is one of the most well-renowned breeds that shows a blue-black tongue. It is such a signature of their breed that the breed standard itself carries over this distinctive feature of the breed. The AKC Breed Standard describes the Chow Chow as having a “solid blue-black tongue, gums, and lips.” Since puppyhood, the Chow Chow bears such deep pigmentation, which makes them different from all the rest of the breeds. Added to that is the thick double coat, a lion-like mane, making them look so great and so distinctive from all other breeds. 
The Shar-Pei is the other breed often found with blue-black tongues. Similar to the Chow Chow, this pigmentation is a breed characteristic. While generally not as dark as that found in the Chow Chow, the Shar-Pei’s tongue usually has bluish-black or lavender colors. Besides this, combined with their particular coat and face wrinkles, makes them a breed that is unique and striking.
Although the Chow Chow and Shar-Pei are the only breeds with a full blue-black tongue as part of their breed standard, most breeds may show some blue or black spotty spotting on the tongue. This is most often caused by an increase in pigmentation called melanin localized in small spots, and generally, this is of little concern.
It’s important to understand that these spots are not a breed characteristic in these other breeds; they are simply variations in pigmentation. Most dogs of these breeds will have entirely pink tongues. However, you might occasionally see these spots in breeds such as:
Worth noting, though, is that Chow Chows and Shar-Peis have completely blue or black tongues as a breed type and hence are considered normal for them. In all other breeds, though, a blue tongue indicates there is a problem—one which we shall discuss in detail in the following sections—and a veterinarian should immediately be consulted when a dog’s tongue suddenly turns blue.
A sudden blue tongue in a dog is a serious sign of impaired oxygen delivery to the tissues. This bluish discoloration, medically termed cyanosis, occurs due to a higher-than-normal amount of deoxygenated hemoglobin (the protein in red blood cells that carries oxygen) in the blood. In essence, the blood isn’t carrying enough oxygen to the body’s cells, resulting in the telltale blue hue, most noticeable in areas with thin skin like the tongue and gums. Cyanosis is a critical condition that demands prompt attention from a veterinarian. Several underlying conditions can lead to this critical lack of oxygen:
The respiratory system plays a vital role in supplying the body with oxygen. When this system is compromised, the oxygen supply to the bloodstream is directly affected, leading to cyanosis. Here’s how specific respiratory conditions interfere with oxygen intake:
Pneumonia: This lung infection inflames the air sacs (alveoli) in the lungs. These air sacs are where oxygen is transferred from the inhaled air into the blood. When they are inflamed and filled with fluid or pus, this transfer is significantly impaired. Less oxygen enters the bloodstream, resulting in low blood oxygen levels (hypoxemia) and subsequent cyanosis.
Tracheal Collapse: The trachea, or windpipe, is held open by rings of cartilage. In tracheal collapse, these rings weaken, causing the trachea to flatten or narrow. This narrowing restricts airflow to the lungs, reducing the amount of oxygen that can be inhaled and ultimately leading to cyanosis. This is especially problematic during exertion or excitement when the demand for oxygen increases.
Lung Tumors: Growths within the lungs, whether benign or malignant, take up space that would normally be used for gas exchange. As the tumor grows, it reduces the functional lung tissue available for oxygen to enter the bloodstream. This diminished capacity for oxygen uptake can cause cyanosis.
Laryngeal Paralysis: The larynx controls the opening to the trachea. In laryngeal paralysis, the nerves and muscles controlling the larynx malfunction, causing it to partially obstruct the airway. This obstruction makes it difficult for the dog to breathe, especially during exercise or excitement, when oxygen demand is higher, leading to cyanosis.
Brachycephalic Obstructive Airway Syndrome (BOAS): Brachycephalic breeds (like Bulldogs, Pugs, and Boxers) have shortened snouts and compressed airways. This anatomy often leads to narrowed nostrils, an elongated soft palate (which partially blocks the airway), and a narrow trachea. These combined abnormalities restrict airflow, making it harder for these dogs to get enough oxygen, predisposing them to cyanosis, especially during exercise or in hot weather.
The heart is responsible for circulating oxygenated blood throughout the body. When its function is impaired, oxygen delivery to the tissues suffers, leading to cyanosis. Here’s how specific heart conditions disrupt oxygen delivery:
Heart Failure: In heart failure, the heart’s pumping ability is weakened. This means that less blood is pumped out to the body with each heartbeat. Consequently, less oxygenated blood reaches the tissues, causing cyanosis. The reduced blood flow also backs up blood into the lungs, leading to fluid accumulation (pulmonary edema), which further impairs oxygen exchange.
Congenital Heart Defects: These are congenital structural irregularities present from birth. For example, a hole between the heart’s chambers (septal defect) allows oxygenated and deoxygenated blood to mix, reducing the overall oxygen content of the blood pumped to the body. Similarly, a narrowed heart valve (stenosis) restricts blood flow, reducing oxygen delivery and potentially causing cyanosis.
Pulmonary Hypertension: High blood pressure in the arteries that carry blood from the heart to the lungs makes it harder for the heart to pump blood through these vessels. This increased pressure can lead to right-sided heart failure, further reducing oxygen delivery and potentially causing cyanosis.
Some blood disorders can also have a direct effect on the blood’s ability to carry oxygen. Methemoglobinemia is a condition in which the iron in hemoglobin is changed, so that it cannot effectively bind to and transport oxygen. This greatly reduces the blood’s oxygen-carrying capacity, resulting in cyanosis. This can be caused by exposure to certain toxins, such as nitrates in some fertilizers, or by certain drugs. Exposure to multiple toxins might also affect the body’s potential to utilize or circulate oxygen, thus creating cyanosis. For instance, substances like nitrates and nitrites act to change hemoglobin into methemoglobin—as earlier explained—and hence hinder oxygen transportation. Similarly, some drugs show similar consequences, especially in vulnerable individuals and at dosages higher than recommended.
Recognizing the signs of cyanosis (a blue tongue in dogs) is crucial. Because a dog’s tongue turning blue indicates a serious lack of oxygen, swift action can be the difference between life and death. Here are the key symptoms to watch for:
Blue or Purple Discoloration of the Tongue and/or Gums: This is the most obvious and defining symptom. The dog’s tongue, normally pink, will take on a bluish or purplish hue. The gums, which should also be pink, will similarly change color. This discoloration is due to the increased concentration of deoxygenated hemoglobin in the blood. Remember, while some dog breeds naturally have blue tongues, a sudden change in tongue or gum color to blue or purple in other breeds is a major red flag. It’s important to note that in some cases, the blue discoloration may be subtle, especially in dogs with dark pigmentation. In these cases, pay close attention to the color of the gums, as they can be easier to assess.
Difficulty Breathing, Rapid Breathing, or Panting: When a dog isn’t getting enough oxygen, their body tries to compensate by breathing faster and harder. This can manifest as:
Coughing or Wheezing: These sounds can indicate problems within the respiratory system, such as fluid in the lungs (pulmonary edema) or airway obstruction. Coughing might be dry or productive (with mucus), while wheezing is a high-pitched whistling sound during breathing. Both can be associated with conditions causing cyanosis in dogs.
Lethargy or Weakness: A lack of oxygen affects all bodily functions, leading to decreased energy levels and weakness. A dog experiencing cyanosis may be unusually tired, reluctant to move, or unable to perform normal activities.
Exercise Intolerance: Because exercise increases the body’s demand for oxygen, dogs with cyanosis will often show an inability to tolerate even mild exertion. They may become easily winded, stop during walks, or collapse.
Collapse: In severe cases, the lack of oxygen to the brain can cause the dog to collapse or lose consciousness. This is a critical emergency. While a blue tongue is a strong indicator of cyanosis, other conditions can cause similar symptoms. A veterinarian will need to perform a thorough examination to determine the underlying cause.
A cyanotic, or blue color of the tongue, is almost always a medical emergency in dogs. If you witness your dog’s tongue suddenly turn blue or purple, especially if he is having difficulty breathing, rapid breathing, coughing, acting lethargic, depressed, or weak, intolerant of exercise, or collapsed, then you should seek veterinary attention immediately. Do not wait. Time is of the essence in cases of cyanosis, since this bluish discoloration indicates a serious and potentially life-threatening deficiency of oxygen to the tissues. Organ failure, brain damage, and even death can occur if there is no timely veterinary intervention.
Several elements ensure that the complaint is urgent. Because cyanosis reflects serious underlying causes, such as heart failure and respiratory distress, toxin exposure, for example, must be found and treated without delay if one is to survive. Once present, the condition of a dog can progress extremely rapidly. What perhaps had started as an almost imperceptible blue tint can result in extreme breathing distress and eventual collapse. Tissue damage can result in irreversible impairment if tissues continue without blood-borne oxygen for too much time.
If you notice these signs, especially the blue tongue, you need to immediately seek your veterinarian’s advice. Clearly describe the situation to them, including the color of the tongue and other signs that may appear. If your veterinarian is not available, then seek immediate veterinary attention from any nearby animal hospital. Do not try to treat your dog at home. Cyanosis is treated by a professional veterinarian and may involve oxygen therapy, diagnostics, and treatment directed at the underlying cause. Keep your dog calm and quiet while en route to the vet.
When a dog presents with cyanosis (a blue tongue or gums), veterinary intervention is crucial to diagnose the underlying cause and initiate appropriate treatment. The diagnostic process typically involves a combination of methods designed to pinpoint the source of the oxygen deficiency. A thorough physical examination is the first step, where the veterinarian will assess the dog’s overall condition, paying close attention to their respiratory and cardiovascular systems. This includes listening to the heart and lungs for abnormal sounds, assessing pulse quality, and evaluating the dog’s breathing effort.
Blood tests play a vital role in evaluating organ function, identifying potential infections, and assessing the blood’s oxygen-carrying capacity. A complete blood count (CBC) can reveal information about red blood cell numbers and overall blood health. A blood gas analysis directly measures the levels of oxygen and carbon dioxide in the blood, providing a precise assessment of the dog’s oxygenation status. This test is crucial in confirming cyanosis and determining its severity. Imaging techniques are often employed in cases where heart or lung issues are suspected. Chest X-rays can reveal abnormalities in the lungs, such as pneumonia, lung tumors, or fluid accumulation. They can also provide information about the heart’s size and shape. Echocardiography, an ultrasound of the heart, offers a detailed view of the heart’s structure and function, allowing veterinarians to identify congenital heart defects or other cardiac abnormalities. In some cases, more advanced imaging techniques like CT scans or MRIs may be necessary to further investigate complex cases or to evaluate specific organs in more detail.
Treatment for cyanosis is highly dependent on the underlying cause. The immediate priority is often to stabilize the dog and improve oxygenation. Oxygen therapy is a cornerstone of treatment for cyanosis, providing supplemental oxygen to increase blood oxygen levels. This can be administered through various methods, including oxygen cages, nasal cannulas, or face masks. Once the dog is stable, treatment focuses on addressing the specific underlying condition. For respiratory issues like pneumonia, antibiotics are typically prescribed to combat the infection. In cases of tracheal collapse, medications to reduce inflammation and open the airways may be used, and in severe cases, surgery may be necessary. For heart conditions like heart failure, medications to improve heart function and reduce fluid buildup are often prescribed. Congenital heart defects may require surgical correction. If a blood disorder like methemoglobinemia is diagnosed, specific medications can be administered to reverse the condition. In cases of toxin exposure, treatment will focus on removing the toxin from the body and providing supportive care.
It’s important to understand that the prognosis for a dog with cyanosis depends largely on the severity of the underlying condition and how quickly treatment is initiated. Early recognition of the symptoms and prompt veterinary intervention are essential for maximizing the chances of a successful outcome. This information is for educational purposes and should not be used as a substitute for professional veterinary advice. Always consult with your veterinarian regarding any health concerns your dog may have.
While not all causes of cyanosis (a blue tongue) in dogs are preventable, proactive measures can significantly reduce the risk of certain underlying conditions. Maintaining your dog’s overall health through regular veterinary checkups is paramount. These checkups allow your veterinarian to detect potential health issues early on, sometimes even before clinical signs become apparent. Vaccinations play a crucial role in protecting your dog against various infectious diseases that can affect the respiratory system, such as canine distemper and kennel cough, which can sometimes lead to complications that contribute to breathing difficulties. A healthy lifestyle, including a balanced diet and regular exercise, is essential for maintaining a strong immune system and overall well-being. This can help reduce the risk of various illnesses that could predispose your dog to respiratory or cardiac problems.
One important preventive measure is avoiding exposure to known toxins. Keep household chemicals, pesticides, and medications safely out of your dog’s reach. Be mindful of potential environmental toxins as well, such as certain fertilizers or contaminated water sources. If you suspect your dog has ingested a toxin, contact your veterinarian or a pet poison control hotline immediately. While some congenital heart defects are not preventable, responsible breeding practices can help reduce their occurrence. Breeders should screen their breeding dogs for known heart conditions to minimize the risk of passing these defects on to their offspring.
A blue tongue in dogs is a serious and potentially life-threatening sign indicating a critical lack of oxygen. If you observe this sign, especially with other concerning symptoms, contact your veterinarian or seek emergency care immediately. Early recognition and prompt intervention are crucial for maximizing your dog’s chances of recovery. While not all causes of cyanosis are preventable, maintaining your dog’s health through regular checkups, vaccinations, a healthy lifestyle, and avoiding toxins can significantly reduce the risk of contributing conditions. Be vigilant about your dog’s health. If you have any concerns, please consult your veterinarian.
