Acyclovir is a synthetic nucleoside analogue. FDA labeling for approved acyclovir products describes inhibitory activity against herpes simplex virus types 1 and 2 and varicella-zoster virus.
Approved acyclovir products are used to treat certain infections caused by those viruses. The exact labeled use depends on the dosage form. For example, topical cream for recurrent cold sores (herpes labialis), and oral products for genital herpes, shingles, or chickenpox. Those labeled uses apply to the FDA-approved products, not to a compounded preparation.
Compounded acyclovir is prepared only pursuant to a valid, patient-specific prescription.