Considerations of Nystatin Roll in Oral Candidiasis Scenario and the COVID-19 Pandemic—A Review

Oral candidiasis is an opportunistic infection usually related to predisposing factors. Oral manifestations in patients affected by COVID-19 have been reported, as the oral mucosa is the gateway to this viral infection. Xerostomia, as well as other oral symptoms, are predisposing factors for the emergence of oral candidiasis after the COVID-19 pandemic. It is a common pathology, but fatal if left untreated. Nystatin (NYS) is the drug of first choice in the treatment of oral candidiasis. Herein, we reviewed the epidemiology of oral candidiasis and its treatments, focusing on the mechanism of action, dosage forms, and NYS efficacy. NYS is an effective drug against oral candidiasis and belongs to Class IV of the biopharmaceutical classification system; however, its low solubility and low permeability may compromise its availability in the oral cavity and, consequently, its pharmacological action. Future perspectives to overcome drug limitations were also addressed and discussed in our review.