My almost 2 year old American bulldog mix, Blue. He started to get really bad bumps and he would itch them and they would bleed, I almost thought he got attacked by mosquitoes or a bee hive I felt so bad I almost blamed the lawn people but I figured out that they were actually hives and started to bathe him in oatmeal based shampoos which seemed to help for a moment. After I did some research I switched his food from a chicken based dog food to a salmon based and wow what a turn around, within a week his hives were getting smaller and smaller and they are now gone. He still gets some here and there but I’ve narrowed those down to flea bites, we live in south Florida and well fleas happen lol. But changing his diet to a salmon based helped him greatly!!!
Oh, one last thing. I can't stress how important flea control is!!! Some dogs are so allergic to flea saliva that one bite can send them spiraling into an itchy outbreak! Please Please Please apply a topical flea medication (advantage/advantix/frontline) EVERY MONTH! It is the most common cause of itching in veterinary patients and is such an easy thing to treat. Even if this is not the primary problem, you can at least help your pet out by not allowing them to contribute to the itching. It can be small things like this that put them over the edge from comfortable to itching and uncomfortable!
I don't advise starting any medications without consulting your vet..that is their job to calculate doses and decided if the medication is appropriate. Allergies are a very difficult thing to control. I know it seems impossible and takes a long time, but the time must be taken to truely rule certain allergies in or out for long term success. Food allergies certainly exist. Signs are usually seen in very young and older patients which include diarrhea, flatulence, puritus (iching), ear infections, etc. They generally occur all year round. Atopic dermatitis (environmental allergies) are generally seen patients greater than 1 year old and are usually only seem at certain times of the year. Signs include puritus, licking/biting at paws, alopecia (hair loss), erythema (redness of the skin), etc. The best course of action is to rule out food allergies first. This is done by feeding a single protein source that the dog has never eaten (like kangaroo or venison). Then after 12 weeks if the dogs seems to get better, you will introduce one new protein source at a time (for an additional 12 weeks each) to determine which ingredient the dog is allergic to and completely cut that out of the diet. If the dog is determined to not have food allergies, then, the cause may be environmental. The dog can not undergo skin allergy testing until they are at least 12 months old because they have not been exposed to all of the seasons and test negative to something they would have eventually tested positive to in the future. Hang in there! There is a method to the madness! Unfortunately, the food and meds do not come cheap. One tip that I have for benedryl is to administer it on a daily schedule determined by your vet. It is not a good medication to treat outbreaks; it needs to be present in the body to prevent histamine release. If you are only giving the medication when your dog is already itchy, it is not being used correctly. That being said, not all patients respond to benedryl. There are other allergy medications out there for use if you vet decides they are appropriate. If you are not able to afford the trials, you can just manage the symptoms with medications when outbreaks occur, but you will never get to the root of the problem. Hope this helps!
Wow, you sound just like me!! My bull dog mix has the same exact issues. I will tell you what has helped me ease his discomfort a little, he still itches but not nearly as bad as before.
Benadryl never worked for him either, now hes on Zyrtec which works better for him. You can also try Allegra, Claritin, Tavist or Chlor-trimeton, I will message you the does amount. I also took him off prescription Royal Canin and put him on grain free Wellness Core (both wet and dry). I also bathe him in Selsun Blue in his "itchy areas."
I would probably be a good idea to get allergy testing done on her since shes so young and having such a hard time. It is costly but in the long run it will save her heath and your peace of mind. Good luck!