Research Progress in the Treatment of Olfactory Dysfunction

Kai Luo ORCID ,  Jianjun Wang ORCID ,  Meng Wang ORCID ,  Jianhui Li ORCID
    Received: 19 November 2025; Revised: 17 April 2026; Accepted: 14 July 2026; Published: 22 July 2026

    Abstract

    Olfaction is one of the primitive sensory functions in humans, and olfactory dysfunction often leads to a decline in patients' quality of life. However, clinical research on the treatment of olfactory dysfunction still faces certain challenges. This article reviews the global research progress in the treatment of olfactory dysfunction in recent years. The main approaches include pharmacotherapy, such as corticosteroids and biologics; olfactory training; surgical treatment; and several novel therapies, including intranasal platelet-rich plasma injection, electrical stimulation of the olfactory system, and olfactory mucosa transplantation. Among the various administration routes, oral, ultrasonic nebulized inhalation, and nasal irrigation therapies have demonstrated superior efficacy compared to intranasal corticosteroids. The researchers compared the efficacy and safety of eight monoclonal antibodies in the treatment of chronic rhinosinusitis with nasal polyps. In terms of improving the olfactory function: Dupilumab ranks first. Olfactory training is applicable for the treatment of post-infectious, post-traumatic, neurodegenerative, and idiopathic olfactory disorders. Compared with traditional training, the novel nasal plug-based olfactory training is more convenient, discreet, and diversified in scent selection, effectively reducing olfactory fatigue and significantly improving patient compliance and therapeutic outcomes. Although its short-term advantages have been demonstrated, further studies are required to validate its long-term efficacy and generalizability. Surgery is a double-edged sword: it can enhance olfactory function, but it may also lead to iatrogenic olfactory impairment. Currently, its main application is still in conductive olfactory disorders, especially for olfactory improvement in individuals with chronic rhinosinusitis accompanied by nasal polyps.

    Keywords

    References

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