To treat a yeast infection, you need an anti-fungal medication. Over-the-counter medications used for yeast infections fall in the anti-fungal class of medications and are available as intravaginal creams, tablets, or suppositories. These include:
Monistat (miconazole nitrate)
Gyne-Lotrimin or Mycelex (clotrimazole vaginal)
Femstat (butoconazole vaginal)
Vagistat-1, Monistat-1 (tioconazole)
I had miconazole on hand for my hen, it worked. I used a feeding tube and syringe to get it into the crop. As the feeding tube is long and you will lose what is in the tube I added more then what I needed so it would make it into the crop. To flush out the tube I switched to another syringe with pasted feed to get that into crop too. I used about the the size of a nickel heaped. 2xs a day. Then massaged the crop to coat the crop inside, and the feed to help get it further into the bird.
It will make the poo greasy looking if she hasn't been able to eat much. Tube feeding her Kaytee bird forumla will help her for eating too. In between medications use the tube to get water into crop and massage to break up anything in the crop. Don't use oils as will coat the crop and make the antifungals ineffective, they won't be able to get to where needed.
Hope that helps, and she gets better soon. *** try not to vomit her she could aspirate and choke on what comes up and could kill her ***