When activated by viral thymidine kinase, acyclovir competitively inhibits viral DNA polymerase, thereby blocking viral DNA synthesis. Although acyclovir does inhibit lytic EBV infection in vitro, it has no effect on latent or persistent infection. Several studies show that oropharyngeal shedding of EBV was dramatically reduced during acyclovir therapy, but EBV replication resumed when antiviral therapy was discontinued. Duration of symptoms did not differ between acyclovir and placebo groups. The anti-inflammatory effects of corticosteroids may shorten the duration of fever, lymphadenopathy, and constitutional symptoms, but controversy exists regarding the the use of steroids for treatment of uncomplicated infectious mononucleosis because the potential risk for steroid inhibition of the cellular immune response.
Studies show no significant difference in duration of symptomatology.
Consequently, drug therapy for EVB-associated infectious mononucleosis is very limited. Acyclovir is not recommended for acute EBV-associated infectious mononucleosis and neither are steroids, except for reducing the edema in patients with impending airway obstruction. In closure, you may want to review Vol 3 Issue 3 January 1996 of the Pediatric Bulletin for the failure to associate chronic EBV-infection with chronic fatigue syndrome.