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An episode of reverse sneezing can be stopped sooner by rubbing under the neck, but there is nothing that will totally stop a dog from reverse sneezing
It is a belief that allergies may cause this but not definite
was the dog showing other signs of allergies?
Here is a link to this which will give you information. over the counter benadryl can be used for allergies but it may not stop the reverse sneeze and you will be drugging your dog for basically no reason if no other signs of allergies exist
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