A total of 41 adults with perennial allergic rhinitis were enrolled in a first double-blind placebo-controlled phase for six months, and treated on a weekly basis with sublingual doses of single individualized homeopathic medicines or placebo. After this closed initial phase, all patients were invited to participate in an long-term open-label controlled phase, in that they would receive homeopathic treatment for the maximum period of 36 months, and the results were compared with the improvement of initial phase. Signs and symptoms scores, rescue medication requirements and quality of life were assessed by questionnaires and personal clinical evaluation by a same independent researcher, before and after each phase. Primary and secondary clinical outcome were, respectively, specific and general allergic signs and symptoms scores. Total IgE titles were performed before and after each phase.