Photobiomodulation in the Treatment of Dysgeusia in Patients with Long COVID: Comment

To the Editor,

We hereby discuss on “Photobiomodulation in the Treatment of Dysgeusia in Patients with Long COVID: A Single-Blind, Randomized Controlled Trial.” ¹ Emerging data indicate that photobiomodulation therapy (PBM), which has demonstrated promise as a treatment for dysgeusia in long-term COVID patients, may be useful in regulating cellular processes and mitigating inflammation. Nevertheless, more randomized controlled trials and clinical investigations are required to confirm the safety and effectiveness of PBM for this use. According to preliminary data from a trial involving 70 individuals with dysgeusia, taste perception significantly improved in the PBM group as compared with the sham group.

The limited sample size and absence of long-term follow-up to evaluate the long-term effects of PBM on dysgeusia are two of the study's weaknesses. Further, the study did not look into the processes behind the therapeutic effects of PBM on taste perception, which limits our knowledge of how this modality helps long-term COVID patients with their dysgeusia symptoms.

Larger carefully monitored clinical trials may be conducted in the future to better assess PBM's effectiveness for dysgeusia in long-term COVID patients. Further, investigations into the fundamental processes by which PBM enhances taste perception may offer important new understandings into possible therapeutic targets for the treatment of dysgeusia in this demographic. Overall, more investigation is required to completely clarify the role of PBM in treating dysgeusia in long-term COVID patients, even though the preliminary results are encouraging.