Methemoglobinemia in Dogs

Category: Blood
Breeds documented: 4
Published sources: 6

Overview

Red blood cells normally carry oxygen using a protein called hemoglobin. In methemoglobinemia, some of that protein changes into a form that cannot bind oxygen normally. This can happen after exposure to certain substances or because of an inherited defect in the system that restores normal hemoglobin. Dogs with the inherited form may have persistently blue gums, reduced energy or occasional fainting during exercise.

Signs to watch for

Blue-tinged gums or tongue
Tiredness or unusually low energy
Reduced tolerance for exercise
Fainting during exercise

Inherited cases may go unrecognized until an examination in adulthood.

Emergency Go to an emergency vet now if your dog loses consciousness.

Diagnosis and tests

Specialized blood testing measures how much hemoglobin is present as methemoglobin. Vets also investigate other causes of blue gums, including heart and lung disease. For a suspected inherited form, enzyme activity testing and DNA tests can help identify the cause. Known genetic tests cover particular variants rather than every possible cause.

Breeds with documented risk

4 breeds

By breed size

1 Toy
1 Small
2 Medium

PomeranianToy · Toy Group
KeeshondMedium · Non-Sporting Group
American Pit Bull TerrierMedium · UKC Terrier Group
German SpitzSmall · Miscellaneous Class

Inheritance

Not yet known
None of the sources we use states how this is inherited in dogs yet.

We've gathered what published sources say about this condition, so you can talk it through with your vet. It isn't veterinary advice: you and your vet know your dog best.