Abstract
Background:
Maintaining platelet (PLT) counts with lower doses of corticosteroid is an important clinical goal in the treatment of immune-mediated thrombocytopenia (IMT) in dogs. However, since some cases of refractory IMT are unresponsive to adjuvant therapies, including immunosuppressive agents and splenectomy, it is necessary to expand the treatment options for IMT. In this study, we evaluated the efficacy of danazol, a synthetic steroid reported to increase PLT counts through immunomodulatory and hormonal effects in human medicine.

Case Description:
This report describes the clinical course of two IMT dogs treated with adjunctive danazol therapy, which remains underexplored in veterinary medicine. In both cases, PLT counts remained difficult to control despite prednisolone (PSL) administration, multiple immunosuppressive agents, and splenectomy. Following the introduction of danazol, PLT counts were maintained within clinically acceptable ranges, and gradual tapering of PSL was achieved for at least 364 days in Case 1 and 716 days in Case 2. No clinically significant adverse effects associated with danazol administration were observed during the follow-up period.

Conclusion:
Our findings indicate that adjunctive danazol therapy may contribute to long-term PLT stabilization in some dogs with refractory IMT that remain poorly controlled after splenectomy. Further studies are warranted to evaluate the clinical utility and safety of danazol as an adjunctive treatment option in canine IMT.

Key words: Adjunctive therapy; Corticosteroid tapering; Immune-mediated disease; Refractory disease; Splenectomy.