A red tongue in dogs can be alarming, considering that the normal color of a dog's tongue is generally for the most part pink. The only exceptions to having a pink tongue are just a few dog breeds like the Chinese shar-pei and Chow Chow (or any of their mixes) which are known for having a distinctive bluish/lavender colored tongue. Getting familiar with the normal color of your dog's tongue and gums is important so that you can quickly recognize early signs of problems. If your dog develops a red tongue, it is best to have the issue investigated by your vet so to exclude several potential medical conditions some of which can be even quite serious.
A Red Tongue in Dogs
A dog's tongue is a muscular organ that is normally kept moist by saliva and is richly supplied by lots of nerves and blood vessels.
Blood supply to the dog's tongue is mainly obtained from the lingual artery, an artery that branches off the external carotid artery (as seen in the picture ob the left). Secondary blood supply to the tongue is obtained from the tonsillar branch of the facial artery and the ascending pharyngeal artery.
When an organ is well supplied by blood, it is known as being vascular. While a dog's skin and coat colors are mostly due to the presence of melanin, a pigment responsible for giving color, the tongue for the most part lacks pigment. Unless the dog in question is a Chinese shar-pei or chow chow, (which have a touch of added pigment in their tongues) the pink color of the tongue is mostly due to the presence of blood running through it.
A healthy, bubble gum pink is therefore the normal color, but if a dog develops a red tongue, then this is quite abnormal. A red tongue in a dog is medically defined as being "injected," explains veterinarian Dr. Michael Salking. What this means is that the tongue becomes red due to an abnormal amount of blood flowing through it.
Causes of a Red Tongue in Dogs
In the case of a red tongue in dogs, it's important to rule out several potential medical problems. In some cases, the red tongue may be caused by high blood pressure, also medically known as hypertension.
High blood pressure means that the force of the blood against the artery walls is too high. This increased flow may therefore cause excessive blood to accumulate in the dog's tongue causing it to become more vascularized than normal and therefore more red due to the increased red blood cells in circulation.
Another worrisome scenario is a dog with a red tongue who is suffering from sepsis. Sepsis is an overwhelming, life threatening infection. Affected dogs may develop hyperdynamic signs associated with an abnormally increased circulatory volume. The affected dog's heart would be racing, there would be a fever and the gums and tongue may turn red during this phase. Obviously septic dogs are very ill and require immediate attention.
Dehydration may also cause the dog's tongue to turn a darker shade of pink The degree of "pinkness" of a dog's tongue, indeed, depends upon the level of hydration, explains veterinarian Dr. Michael Salkin.
A tongue that is purple or assumes a bluish tint may be indicative of poor oxygenation due to underlying heart problems and requires immediate vet attention. Affected dogs may be breathing fast or hard and the lungs may be filling with fluid. A purple tongue is alarming because it can lead to cardiac arrest if the dog's oxygen levels happen to drop too low, explains veterinarian Dr. Drew.
Other possible causes of a red tongue in dogs may include carbon monoxide poisoning, exposure to toxins, allergies, stomach torsion, overheating as seen in a dog who has been exercising strenuously (red tongue in this case may be temporary), licking abrasive surfaces or consuming something leeching a red dye. In some cases, a red tongue or oral mucous membranes with red dots may be a sign of heat stroke. Suspect heat stroke if your dog has been in hot weather and his rectal temperature is higher than normal (above 103° F or 39° C).
"Heat stroke can lead to increased viscosity (due to dehydration) and hypercoagulation of the blood and widespread organ failure." ~Dr. John, veterinarian.
At the Vet's Office
Because the causes of a red tongue in dogs can be various, it is best to see the vet. An emergency vet should be sought at once if it is after hours and the dog is acting sickly.
Once at the vet's office, the vet will ask several questions and may assess the dog's vitals, checking the dog's respiratory rate, heart beat (checking for heart murmurs) and the color and perfusion of blood to the gums.
Emergency situations such as heat stroke require the dog to be stabilized and monitored. Dogs affected by heatstroke will receive intensive care and blood tests for evaluating clotting parameters. This is to monitor for a serious complication of heat stroke known as Disseminated Intravascular Coagulation.
In non-emergency situations the vet will inspect the tongue. The redness at times may be a sign of irritation caused by trauma. A dog's tongue may get irritated when a dog chews on a bone or rough toys, or from friction when licking the carpet. Exposure to chemicals, ice cubes, an electrical burn, burns from hot food or water can be other culprits, explains veterinarian Dr. Ralston.
Treatment of a red tongue in dogs varies based on the underlying cause. The vet may have to run several diagnostic tests to rule out or confirm the trigger. Tests may include bloodwork specifically a CBC (complete blood count), chest x-rays and other tests the vet may deem necessary based on the dog's medical history and presentation of symptoms.
In some cases, especially when the dog appears bright, healthy, happy and alert, the vet may not find an underlying cause despite the onset of red tongue. In some dogs, a darker pink color may be just be a normal anatomical feature.