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Dr. B.
Dr. B., Cat Veterinarian
Category: Cat Veterinary
Satisfied Customers: 21462
Experience:  Small animal veterinarian with a special interest in cats, happy to discuss any questions you have.
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My cat is losing s hair I put on flea meds but it doesn't

Customer Question

my cat is losing his hair I put on flea meds but it doesn't help he licks these spots till they bleed he stays in the house my other cat is fine
Submitted: 1 year ago.
Category: Cat Veterinary
Expert:  Dr. B. replied 1 year ago.

Hello & welcome, I am Dr. B, a licensed veterinarian and I would like to help you with your wee one today.

How long has he had these signs?

Where is he scratching/grooming specifically (ie neck, belly, etc)?

What brand of flea treatment did you use (since not all are very effective)?

Are you seeing any changes to his skin (ie pimples, pustules, scabs, sores, ulcers, redness, dander, or crusting)?

Has he had any diet change in the 4-6 weeks before this started?

Expert:  Dr. B. replied 1 year ago.

Hi again,

I have not heard back from you but do want to leave my thoughts about poor Jack.

Now in his case, it sounds like we may have a flea allergy dermatitis lurking. And while its good that he is up to date with flea treatment, it is important to note that treating for the fleas is only half the battle. This is because these cats are actually allergic to the saliva in a flea’s bite. That means that even after the fleas have left, the cat’s immune system will keep reacting to the saliva. And that is what causing the itchiness weeks after we have cleared all the fleas. As well, being that it is an allergy, this is why we can see one cat well an the other terribly irritated.

So, further to treating monthly for fleas in sensitive cats, we do need to address that immune reaction. If it is severe, then we do often need long acting injectable steroids from their vet to settle this reaction. Though for more mild cases, we can try antihistamines. Most commonly we use Benadryl/Diphenhydramine (More Info/Dose @ A low dose (ie. 0.25mg per pound of their body weight twice daily) can just be enough to reduce that allergic irritation. Alternatively, you can also use Cetirizine (just 5mg for a cat) once daily. For either, we like to keep the dose low, since it can cause drowsiness (just like people). And of course, these shouldn't be used if Jack has any known health issues or is on any other medication without speaking to your vet first.

Overall, it sounds like Jack has flea allergy dermatitis. You were right to treat for the fleas but we need to address the allergy too. Therefore, we'd want to take the above approach at this stage +/- have his vet treat him with long acting steroids to settle that irritation so he can stop itching and let his skin heal.

All the best,

Dr. B.


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