Expert: Dr. Louis N. Gotthelf - 8/28/2009

Question
QUESTION: Hello, we always use frontline plus and heartgard plus on are two dogs (one is a pomeranian about 9 lbs, other a terrier mix about 40 lbs). We recently moved into a new apartment and have noticed fleas! We have never had fleas before and our oldest dog is 6 years. We have always been consistent with treating for fleas because we know of the possible danger they pose, not to mention discomfort. Well, the dogs are current on their flea and heartworm treatments yet I continue to see 3-4 fleas on each of them per day.

As soon as we noticed the fleas we got a product called Knockout by Virbac and sprayed the fabric and carpet in the apartment. It has been 3 days since we did this and we still see fleas. Is this normal to see fleas even after consistently treating our dogs with frontline plus and spraying the environment with Knockout? Now, dont get me wrong, we have to really really search for the fleas in order to see them, they are not out in the open or easy to find but they are still there. Is there anything else we should be doing to help kill and prevent further fleas?

One main concern is that our Pomeranian is itching alot where it never itched before and on his belly he has little red bites marks, which is odd because frontline says it repells fleas. Shouldnt the frontline prevent the fleas from biting? The pom has the itching and red bites. We have given him benadryl at a dose of about 1 mg per pound and it seems to help a bit but the pom still itches, any helpful tips to relieve the bite itches? The other dog, the terrier mix, has allergies and normally itches alittle but ever since we moved and the fleas are present that dog is itching more as well. We give him benadryl as well at a dose of 1.3 mg per pound. The terrier mix has a few bite marks on his back legs and back belly which again is odd because I was under the impression the frontline prevented biting and repelled fleas. Any ideas?

My main concerns are killing the fleas, preventing the reactions both my pets are having from the bites (itching and red marks), and making sure the pets are free of fleas so they do not have the discomfort. To recap, we use Frontline Plus (which they both received 4 days ago) and Heartgard Plus (know it does not do anything for fleas but we make sure to cover all basis) and have sprayed our house fabric and carpet with Virbac Knockout Area Spray but still see fleas after treating almost 5 days ago. What should we be doing we are not? How can I help get the fleas off the pets and relieve their skin itches and bite marks? Please help. We have never had fleas as we always be sure to keep our pets treated because we care for thier comfort and health and this sudden flea appearance is scarey to us. We dont see fleas unless we really look but seeing just a few is a worry. Thanks for your help.

ANSWER: I deal with this exact problem all summer long in the SOutheast.  Fleas inthe environment are the problem here.  YoOu need to be very diligent in spraying the carpeting, the outside environment, the furniture and washing the bedding regularly (every 2 weeks for a minimum of 3 applications).  In the flea life cycle, there is a cocoon stage attached to carpet fibers and grasses, which none of the insecticide products can kill.  So when these cocoons open and baby fleas emerge, they want blood, so they jump on the dogs.  Frontline Plus is very effective at killing these baby fleas and preventing flea larvae from maturation to the cocoon stage, but you will occasionally see a few fleas that have jumped on and have not yet been killed.  With time and indoor confinement you will see the number get less and less as all of the cocoons hatch out.  No new cocoons will be forming.

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QUESTION: Thanks for your help. We have been consistent as you say with treating the carpets and fabric items in the home. We live in an apartment on the third floor so we have no grass. However, we are spraying out deck furniture which is fabric. So far we have been seeing less and less so it must be working. We live in chattanooga, tn so as you say in the south fleas are a problem. We haved lived in tennessee for over 10 years and NEVER had flea problems until we moved 2 weeks ago! We are always diligent on keeping our dogs healthy with preventative meds. I had two more questions for you. 1-one of our dogs has had a mild skin rash from the fleas and continues to itch, is there anything we can do for him in terms of a medicine or shampoo or ointment? We have used benadrly and it works a bit but is there a topical treatment we should use? The problem is he seems to itching pretty often and his itching is making the spots where he was bit get worse so we want to stop it before it become a problem. 2-on an unrelated concern, our other dog (1 year, terrier mix, 40lbs, current on vet care) has been shaking his head for a while now. I have taken him into the vet 2 times to get the test done to see if he has an ear infection (microscope looking at the wax) and both tests came back negative as in he does not have any infection. He does not itch very much but he shakes his head as if he was trying to get something out. The vet said there is no infection and not any object in his ear. Any ideas? He is acting fine and it does not affect his life in any way but I wonder if there is a reason he shakes his head often. He has been cleared to be healthy from a vet 2 different times so do you have any idea why he is shaking his head more often than normal? Thanks.

Answer
The answer to the first question is that your dog can get on a short course of steroids for the itching.  Flea bites can cause itching for up to 30days after the last flea bite.  This is a delayed hypersensitivity (also called a type IV).

The second question has a very simple explanation.  There can be severe itching in the ear with out having an infection.  Allergic dermatitis also affects the skin of theear canal.  There are steroid drops, like Synotic that can be very useful for that.  There is something called referred pain that means when there is a throat problem the pain can radiate into the ear causing pain and discomfort.