The prophylactic role of intravenous and long-term oral acyclovir after allogeneic bone marrow transplantation

Eighty-two patients were randomly allocated to receive intravenous acyclovir 5 mg kg–1 t.d.s. for 23 days followed by oral acyclovir 800mg 6-hourly for 6 months or matching placebos after allogeneic bone marrow transplantation. Herpes simplex and varicella zoster virus infections were significantly reduced during the period of administration of acyclovir. No reduction in cytomegalovirus infection was demonstrated. The drug was not toxic.