Prednisolone does not improve olfactory function after COVID-19: a randomized, double-blind, placebo-controlled trial

Area of Science:

• Otolaryngology
• Infectious Diseases
• Pharmacology

Background:

• Persistent olfactory dysfunction is a common sequela of COVID-19.
• Limited evidence exists regarding the efficacy of pharmacological interventions for post-COVID-19 olfactory disorders.
• Oral prednisolone has been proposed as a potential treatment, necessitating clinical investigation.

Purpose of the Study:

• To evaluate the efficacy of a short course of oral prednisolone in patients experiencing persistent olfactory disorders after COVID-19.
• To compare objective and subjective olfactory and gustatory functions between prednisolone and placebo groups.

Main Methods:

• A randomized, double-blind, placebo-controlled trial was conducted with 115 adult patients.
• Participants received either oral prednisolone (40 mg daily for 10 days) or a placebo, alongside olfactory training.
• Olfactory function was assessed using the Sniffin' Sticks Test (TDI score) at 12 weeks post-treatment.

Main Results:

• No significant difference in objective olfactory function (TDI score) was observed between the prednisolone and placebo groups at 12 weeks.
• Both groups showed similar improvements in olfactory function, indicating no added benefit from prednisolone.
• Secondary outcomes, including gustatory function and self-reported symptoms, also showed no significant differences between the groups.

Conclusions:

• Short-term oral prednisolone treatment is not effective in improving olfactory function in patients with persistent post-COVID-19 olfactory disorders.
• The findings suggest that prednisolone should not be prescribed for this condition.
• Further research may explore alternative or combination therapies for post-COVID-19 olfactory dysfunction.