Feline sporotrichosis is an endemic disease in Rio de Janeiro, Brazil, where zoonotic transmission of Sporothrix spp. has been reported since 1998. Itraconazole (ITZ) remains the first choice for treating this disease in cats. However, there have been reports of therapeutic failure and a long-term endeavor. Potassium iodide (KI), considered in the past as a drug with variable effectiveness in cats with sporotrichosis, arises as an important option in the treatment of cats from the endemic area of Rio de Janeiro. In order to evaluate the effectiveness of the association of ITZ and KI in naive cats with sporotrichosis, a prospective cohort study was conducted on 30 cats receiving ITZ 100 mg/day and KI 2.5 mg-20 mg/kg/day. Clinical and laboratory adverse effects were assessed once a month according to the standard care protocol. The cure rate was 96.15% within a median of 14 weeks of treatment. Adverse effects were observed in 50% of cats and were managed with a temporary drug suspension and/or a hepatoprotective therapy. The association of ITZ and KI emerges as an effective option for the treatment of feline sporotrichosis.