Oral candidiasis frequently occurs in HIV-positive patients especially in those with advanced disease. To date, common anti-mycotic drugs are unable to prevent relapses and alternative therapy is necessary to reduce disabling effects. With the aim of verifying whether thymic hormone extract may be efficacious in these subjects, we enrolled 10 HIV-positive patients with recurrent and/or persistent oral candidiasis to be treated with thymopentin (oral inhalations). All patients benefited from the topical use of thymopentin, and in all cases there was marked increase in salivary secretory IgA which possibly accounted for the candidiasis improvement.