I'm sorry to hear of this with Doodles. Can you tell me which antibiotic was prescribed? Ketoconazole dosed at 5 mg/lb once daily for a month plus shampooing twice weekly in a chlorhexidine- and ketoconazole- or miconazole-containing shampoo usually is quite effective when addressing widespread yeast. Here's my more complete synopsis of yeast infection for you:
1. Any underlying cause (allergies/food intolerance, atopy, e.g., endocrinopathy/hypothyroidism, e.g., keratinization defect/seborrhea) must be identified and corrected.
2. For mild cases, topical therapy alone is often effective. The patient should be bathed every 2-3 days with shampoo that contains 2% ketoconazole, 1% ketoconazole/2% chlorhexidine (https://www.amazon.com/Keto-C-Ketoconazole-1-Chlorhexidine-Shampoo/dp/B00Q34IY6Y), 2% miconazole, 2-4% chlorhexidine, or 1% selenium sulfide (Selsun Blue). Shampoos that have two active ingredients provide better efficacy. Treatment should be continued until the lesions resolve and follow-up skin cytology reveals no organisms (approximately 4 weeks).
3. The treatment of choice for moderate to severe cases is ketoconazole or fluconazole 10 mg/kg orally with food every 24 hours. Treatment should be continued until lesions resolve and follow-up skin cytology reveals no organisms (approximately 4 weeks).
4. Alternatively, treatment with terbinafine 5-40 mg/kg orally every 24 hours or itraconazole (Sporanox) 5-10 mg/kg every 24 hours for 4 weeks may be effective.
The prognosis is good if the underlying cause can be identifed and corrected. Otherwise, regular once- or twice-weekly antiyeast shampoo baths may be needed to prevent relapse. Please respond with further questions or concerns if you wish.