People with the extreme sensitivities that come with mold/MCS often cannot handle having pets in the house. And I am so sorry for that. Thankfully, my family has an Australian Labradoodle, which is hypoallergenic all the way. Like- super hypoallergenic. They can be pretty expensive, but we were thankfully able to be a part of a guardianship program. We got our dog several years before mold happened and we are so glad we didn’t have to give her up. I know that that is a very rare case for ‘moldy people’, and so I’m really sorry if that is the case for you. 😦
However, if you are able to have a dog, it’s important to remember that they, too, lived with you in your moldy house with you. Our dog, Zoey, started having seizures. No known dog in her bloodline had ever had them before, and neither had she. The first thing we did was try to keep her out of the moldy house as much as possible, and we also began giving her Chlorella. (A dog-sized dose, of course). Thankfully, that seemed to help, she stopped having seizures. 
Another important thing to do when you have a dog who had lived with you through mold, is to bathe them regularly. Not only does their fur hold allergens that they pick up outside, but it also holds mycotoxins. You see, just like you, your dog’s body is releasing mycotoxins through their skin as their body gets rid of the mold-toxins in it. On you, it washes off when you shower everyday, but on your dog, they not only don’t bathe as often as you, but their fur hold the mycotoxins even more! So, yes, bathing them regularly is important, even if they, like Zoey, don’t like baths.
One more thing to be aware of is any medications or soaps that you put on your dog topically. They are full of chemicals that can set you off! I could not figure out why in the world school was so hard for me one day. And then it hit me as I looked at my dog laying next to me: she had just been given ear powder to prevent ear mites! Ah, so it wasn’t my brother’s deodorant like I had been suspecting! (Correction: late we realized that it bothered me as well, and that it had been both of them:) ) So, while we are still trying to find ways to give her the medications she needs without causing sickness to ourselves, we have found a few things that work. At all possible times, we try to give her medications she can take orally, instead of the topical ones. We also have found a soap that effectively cleans her, without harm to us:
Also, as for alternatives to ear powder as specified as a problem above, we have been using the tea tree essential oil, mixed with a carrier oil. It isn’t a perfect fix, as it cannot be applied to places she can reach with her tongue, like her paws. It is important, also, to apply the oil often… every few days to be safe. We didn’t at one point and it resulted in a very unhappy ear and dog.
R5:3-5 