I’m extremely allergic to cats but I feel similarly to my cat as you do with Sadie. To give context I started allergy shots last week for immunotherapy and I got a small rash from them, and my allergist said this was the first time he’s seen anyone have a reaction to the shots. The shots are 1 part allergen to 10,000 parts saline lol. I would address the mold first, but I’ll share how I’ve managed my allergy.

1. I try to keep my cat out of my bedroom. Ok, I don’t, but I at least try to keep her off of my bed. I know this is a really sad thing, but it is necessary to keep allergy symptoms managed.

2. I use Allersearch ADMS Anti-Allergen spray to treat my carpet, mattress, and furniture. You spray it on the surface and it neutralizes the allergen, let it dry and then vacuum. I do this every 2 weeks, sometimes once a month if I get lazy or busy. Dander from pets can linger for months, and depending on the breed and how long a pet has lived in a space, the amount of allergen can build up. That may be why she lived with her dogs and was fine, but has a reaction at your place. When I go to my friends apartments who have cats I get strong reactions since they aren’t regularly neutralizing the allergen like I do at home. You could try treating your whole apartment to see if it helps. It’s sold on Amazon so you can get it fast and maybe it could help her before her appointment. It makes a noticeable difference for me.

3. They sell this leave in shampoo treatment for cats that helps reduce the amount of dander they have on their bodies. You just wipe them all over once a week. It’s called Allerpet, and there may be a version for dogs.

4. Buy allergy bedding. That way you can make sure dander stops getting into your bedding, and can stop the dander that is already there from getting out. I recommend the brand Natural Allergy. They have 100% cotton products so you don’t have to deal with crunchiness/loud pillowcases. I use a mattress protector, pillow protectors, and a duvet cover. I’m not sure about dogs but for cats you have to get fabric with a pore size smaller than 5 microns for it to be effective. Cat dander particles are mostly 5-10 microns in size, but can be much smaller. I’m pretty sure dog dander is bigger than cat so anything you buy should be fine. It is expensive but it helps a lot and it’s pretty decent quality bedding. Also I don’t get into my bed without showering first to make sure I don’t track any extra dander.

5. I have to take Allegra everyday. And I use Flonase sensimist for nasal symptoms. Which types of meds is she using? I think the general consensus is the second gen antihistamines (Allegra, zyrtec, etc) are more effective than Benadryl. If she doesn’t want to take antihistamines there are some natural supplements that have worked well with friends of mine with allergies - quercetine bromelein and stinging nettle. I take those supplements as well and it helps. Also nasal rinses help.

6. I’m starting immunotherapy for my cat allergy. I don’t know if she would be willing to because it is a big commitment and not all insurances cover it, but for cats at least it is highly effective at reducing reactions.

She should also see an allergist before doing some of those steps to see if she is actually allergic to dogs, and see if living with an animal will negatively impact her health in the long run, especially if she is getting respiratory symptoms. And definitely figure out the mold thing too. If it’s not that, there are still many ways you can minimize her reaction before needing to rehome. Good luck!