Oh, I know exactly about having a lab (black instead of chocolate however) and trying to figure out the cause of the allergy. He had a constant need to itch his back so much it caused crusty scabs to appear. We took him to the vet (two different ones over the years) to try to figure out what was causing it. First doc thought diet. We switched to high protein, easily digestible fat dry food...no help. Second doc tested for all kinds of things...skin allergy tests, no fleas since he had a preventive every 3 months, ear mite medicine helped his ears.
Here is a helpful site-oatmeal bath or medicated dog bath might help, coconut oil is listed as potential help, others.
Good luck! I hope your vet is more current about ways to identify source and effective treatment options than the two vets I tried locally. Labs are the best- I've had two and likely at least one more in the near future
Skin allergies are fairly common in dogs. They are not typically something to get too concerned about. With proper care and treatment, they shouldn't cause much of a problem. However, if left untreated they could lead to more severe health problems. You should consult with your veterinarian...
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