Efficient acyclovir use depends on early initiation, careful renal dosing, and hydration to prevent nephrotoxicity.
Initiate within 72 hours of rash onset for varicella or prodromal symptoms for HSV to maximize lesion resolution and reduce complications.
Encourage ≥1 mL/kg/hour urine output; administer IV fluids when using high-dose IV regimens to prevent crystalluria and acute kidney injury.
Use extended intervals for eGFR <50 mL/min/1.73 m² and consult neonatal dosing tables (e.g., 20 mg/kg IV q8h for neonatal HSV).
Confusion, tremors, or hallucinations may indicate neurotoxicity—check renal function, adjust dose, and consider discontinuation if severe.