[Action of para-aminobenzoic acid and its combination with acyclovir in herpetic infection].

The effect of para-amino benzoic acid (PABA) on the virus of Herpes simplex (VHS-1, strain L2) was studied and it was shown to be active in vitro and in vivo. The action of PABA was virucidal in the culture of the cell-free virus-containing material. It lowered the death rate of the laboratory mice with experimental herpetic encephalitis (intraperitoneal contamination) at the average by 40 per cent and increased the mean life-span of the animals significantly decreasing the virus titre in the mouse brain. PABA was not toxic with respect to the Vero cells thus not preventing the virus-induced cytopathic effect in the cultures. However, PABA showed high ability to potentiate the antiherpetic action of acyclovir (Zovirax, acycloguanosine) in the infected cultures when acyclovir was used in inactive concentrations.