The purpose of this review is to go over the only therapy for olfactory loss supported by level 1a evidence that is currently available, which is olfactory training. This therapy is widely underutilized and has the potential to help many patients with olfactory dysfunction who are otherwise offered no management options.
We will review the rationale, clinical studies, and quality of the evidence regarding olfactory training, specifically the olfactory system's inherent ability to regenerate, the plasticity of the system, and the multiple protocols and modifications of protocols present in the literature.
Olfactory training is an effective therapy for some patients suffering from olfactory loss, and, while we do not yet know the optimal duration or number of odorants or exact patient population it may be most beneficial for, as an extremely easy, self-driven therapy with no significant side-effects, it should be consistently offered to this patient population.
Department of Otolaryngology – Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, USA
Correspondence to Zara M. Patel, MD, Department of Otolaryngology – Head and Neck Surgery, Stanford University School of Medicine, 801 Welch Rd., Stanford, CA 94305, USA. Tel: +1 650 723 5651; e-mail: firstname.lastname@example.org