When topical therapy is not enough, veterinarians may use oral antifungals, especially for widespread skin involvement or severe, recurring flares. These medications can be very helpful, but they are not “no-risk,” and monitoring matters. A retrospective study in dogs documented adverse effects associated with ketoconazole use, reinforcing that systemic therapy should be vet-guided and individualized (Mayer, 2008). Dogs with liver disease, multiple medications, or appetite issues may need extra caution.
At home, watch for appetite drop, vomiting, diarrhea, unusual tiredness, or yellowing of the whites of the eyes, and report these quickly during oral therapy. Avoid adding new supplements or treats during the first week unless cleared, so side effects are easier to interpret. If a dog has had prior reactions to medications, share that history before starting pills; it can change the choice of drug and the monitoring plan.