Severe flea infestations can cause blood loss anemia. Shock & death are a big risk.



I have a small dog who has been passing out! She comes out of it when I pick her up . Yesterday she went into convulsions but again snapped out of it when I picked her up. The fleas are really bad this year, she

was okay for one day after bathing , I sprayed the carpet and all was okay until she went outside and again was covered with fleas. Is it possible this can be caused by a reaction to the flea bites?


Dr. Nichol:

Your little girl is lucky to have an owner who cares about her. She has a serious reason for fainting which may or may not be related to her flea problem. Let’s start with an understanding of fainting and convulsions; then we’ll talk about fleas.


The truth is that the list of causes for convulsions and fainting is quite long. The possibilities that I would consider first are: Low blood sugar, anemia (low number of red blood cells), epilepsy, heart disease, and liver disease. There may be other considerations if her physical exam suggests them. So how does that fit in with fleas? A large number of fleas can drain a small dog of a lot of blood. This could cause her to feel weak and pass out just because she would not have enough red blood cells to carry oxygen to her brain. The physical stress of all those parasites  could also be making her blood sugar drop resulting in seizures but it’s unlikely. So her seizuring is a great concern all by itself.


Here is the best way to proceed: Explain your dog’s history to her doctor in detail. Be prepared to have some lab work like a blood count, a blood chemistry profile, and a urinalysis. These will answer most questions regarding the severity of blood loss and the function of her internal organs. While the hospital’s technician staff is working on answers the veterinarian will be starting treatment. Given the number of fleas you describe I suspect that a blood transfusion may be necessary. She may also need i.v. sugars. This should get her stable.


Your girl’s fleas are also a major priority but they must be eliminated carefully. Potent insecticides would  kill the fleas but could also be the physical stress that pushes your frail little girl over the edge. Medical management of this puppy must happen fast and it has to be done carefully. Your mission is to get your dog’s life saved quickly. Please do not delay in seeing your veterinarian.