I know this one time my dog went out to go potty it was dark so I just stood at the door when she came back in she had a bump on her face that was so big I swear it was a spider bite I gave her a Benadryl an it went away I couldn't believe it did you try any Benadryl? It 1 mg per pound an they come in 25 mg so Franklin is 50lbs. So I give him 2. But if its the first time you are giving it I would just go with half the dose an then a couple hour later give the rest the first time I gave Franklin Benadryl I only gave him a half an he was so sleepy an now that he's taken some he can have a regular dose now so just be careful if you try it good luck hope she gets better soon