Amylmetacresol/2,4-dichlorobenzyl alcohol, hexylresorcinol, or carrageenan lozenges as active treatments for sore throat

Morokutti-Kurz, Martina; Graf, Christine; Prieschl-Grassauer, Eva

A cell-based assay in a 96-well format was used to test the antiviral effectiveness of the different lozenges solutions against HRV1a/8 and Coxsackievirus A10. Here, the virus was preincubated with a semilogarithmic dilution series of the respective test samples or control for 30 minutes at room temperature (RT; prophylactic treatment) before it was added to HeLa/RD cells for infection. After an infection period of 30 minutes at RT, cells were washed with medium and then cultured at 33°C (HRV) or 37°C (Coxsackievirus), hereby maintaining the same concentrations of active agent as in the prophylactic treatment. The antiviral effectiveness of the test samples was assessed by determining cell viability using resazurin fluorescent dye when >90% cells of a control infection in the absence of any active agent have died. An incubation of cells with the same dilution series in the absence of viral infection was performed to monitor a potential toxicity of the treatment. To enable direct comparison of the antiviral effectiveness of the lozenges, the half maximal inhibitory dilution (ID 50 ) value of each sample was calculated for a sigmoidal dose-response model with XLfit Excel add-in version 5.3.1. From this value, corresponding iota-carrageenan concentrations were calculated for the lozenge #1.