Dogs & Anemia: Effects and Treatment of IMHA

Dogs anemia is not a specific disease but the result of some disease in progress. Anemia is a reduced number of red blood cells or hemoglobin or both.

What is IMHA

Immune- mediated hemolytic anemia (IMHA), formerly known as autoimmune hemolytic anemia or AIHA, is a "secondary" disease that occurs when the body's own immune system attacks it's red blood cells. IMHA refers to all anemias that occur when the immune system inadvertently destroys its own blood cells. IMHA is secondary to an immune attack directed against an underlying condition. The red blood cells become quickly coated with tiny antibody proteins, essentially marking these red blood cells for destruction.

Types of anemia

There are two classifications of anemia. In the first, the body loses blood faster than it can be regenerated but your pet is still able to produce new red blood cells in its bone marrow. In the second, your dog has lost the ability to make new red blood cells in the bone marrow. There are so many different types and causes of anemia. The categories of anemia can be caused by trauma, cancer, immune-mediated disease, which is a disease in which the body attacks its own cells or organs, infectious disease, toxins, genetic defects, inflammatory disease, iron deficiency, drug reactions, kidney failure, and generalized chronic illness. Blood loss caused by trauma or injury, parasites like fleas, ticks and worms, and diseases that prevent the blood from clotting. Common areas for bleeding include the digestive tract and if your dog is suffering from hookworm or heartworm. There is no gender or age predisposition for anemia. Most anemic dogs act weak or tired. Skin may appear to be pale with yellow discoloration. Many dogs with IMHA have symptoms like vomiting or loss of appetite. Depending on the underlying cause of the anemia, your pet may show some or all symptoms and signs. Some pets may not show any signs at all.


Dog anemia symptoms include pale gums, fatigue, listlessness, loss of appetite, and appear weak and depressed. Your pet may also sleep more than usual and stop grooming themselves. Anemic dogs must breath faster to keep their bodies oxygenated and so, their heart beats faster. They often have low energy levels. More serious signs to watch for are episodes of collapse, seizures, evidence of blood loss, blood in urine or feces, vomiting, weight loss and yellow discoloration of the skin.


Immune-mediated hemolytic anemia is usually diagnosed based on suspicion and the absence of any other specific causes for anemia.The evaluation of an anemic dog consists of blood work, x-rays, ultrasound, bone marrow examinations, and other diagnostic tests.


A dog with IMHA is often unstable. Improving oxygen delivery to cells can prevent the consequences of multiple organ dysfunction. Severe cases of anemia require blood transfusions to stabilize your dog while the cause of the anemia is diagnosed and the underlying cause is treated. It is not unusual for a severely affected dog to require many transfusions. Mild cases of anemia do not require a blood transfusion. Supportive care is needed to maintain the dog's fluid balance and nutritional needs. Mild to moderate cases of anemia are treated with blood-building vitamins and minerals. In more severe cases, the spleen enlarges as it finds itself processing far more damaged red blood cells than it normally does and may need to be removed. Suppressing the immune system's rampant red blood cell destruction is most important. In the case of IMHA, there is no known cause. Treatment for this condition is Prednisone (corticosteroid hormones) which slows the bodies attack on the red blood cells. Supplementation with stronger immune suppressive agents is necessary if no response is seen with cortisteroids. The most common medications used in this case are azathioprine and cyclophosphamide. Some dogs do not respond to treatment, but if your dog responds, then the prognosis is good.