Ever since I was stung several years ago by a wasp while picking up apples in the backyard, I worry that one of these days my Chihuahua "Little Shannon" will get stung. She loves looking for apples in the yard and it seems that so do the wasps.
I was surprised at how much a wasp sting hurts, can't imagine what it would be like for a small dog such as a Chihuahua. Doing a search on the internet I found that giving 1 mg of Benadryl for every 1 lb of the dog's body weight can prevent a potentially serious allergic reaction in dogs that have been stung by bees or wasps.
If a stung dog seems to be getting worse, has trouble breathing or is stung in the mouth or tongue take the dog to the vet immediately.
Hmm, now that's good to know.