CASE SUMMARY
Anosmia tends to manifest during the early stages of coronavirus disease 2019 (COVID-19).1 A 42-year-old male patient was hospitalized for intermittent fever, dry cough, and malaise. On the third day of hospitalization, real-time reverse transcriptase–polymerase chain reaction analysis of his nasopharyngeal samples yielded a positive result for severe acute respiratory syndrome coronavirus 2; thus, the patient was diagnosed with COVID-19 and treated with 400 mg lopinavir every 12 h for 2 weeks. After 1 week of hospitalization, the patient reported losing his sense of smell in both nasal cavities. Based on olfactory function tests, he was diagnosed with complete anosmia and olfactory function tests evaluate the degree of anosmia more objectively,2 which is helpful during the follow-up of patients to evaluate treatment response. Magnetic resonance brain imaging showed no abnormalities (Figure 1). Thereafter, treatment with 5000 IU of Citoneurin (Vitamin B1 [thiamine hydrochloride], 100 mg/day; Vitamin B6 [pyridoxine hydrochloride], 100 mg/day; Vitamin B12 [cyanocobalamin], 5000 mcg/day) orally and olfactory training, which consists of inhaling identified flasks containing cinnamon, cloves, and lavender for 15 minutes/day were prescribed. Repeated exposure to an odorant may modulate the regenerative capacity of the olfactory receptors.3 Subjective signs of anosmia began to improve 12 days later. Two weeks after lopinavir therapy, the patient recovered from most symptoms of COVID-19; and forty days after initiation of B-complex vitamins and olfactory training, he recovered from anosmia. We conclude that B-complex vitamins and olfactory training may be effective for the treatment of COVID-19–related anosmia.