Specific immunotherapy is a very powerful tool which is currently under-utilized in the treatment of allergies. Sublingual immunotherapy (SLIT) has many advantages over subcutaneous immunotherapy (SCIT), and has been well proven to work for many pollens and dust mites. Multiple studies have shown SLIT improves symptoms and reduces the reliance on medications. Sublingual treatment has been studied in Europe and is endorsed by the World Health Organization Committee on Immunotherapy as a viable alternative to SCIT. Conclusion: SLIT offers another option for patients who are not currently candidates for subcutaneous immunotherapy. Because of improved safety, convenience and compliance, sublingual immunotherapy should be used as a first-line treatment option. Copyright (C) 2003 S. Karger AG, Basel.