C difficile risk
Oral Bioavailability
Poor (Less than 20%)
$0.60/day (PO) $35.40/day (IV)


Serious Infections
(e.g. CNS and Disseminated Zoster)
10mg/kg IV q8h

800mg PO 5 times per day

Prophylaxis dosing varies by indication

eGFR 0 - 10eGFR 10 - 25eGFR 25 - 50eGFR > 505mg/kg IV q24h, or half of regular dose q24h10mg/kg IV q24h10mg/kg IV q12h10mg/kg IV q8h (Regular dosing)

2.5-5mg/kg IV q24h

Give dose after dialysis on dialysis days

Peritoneal Dialysis 5-10 mg/kg IV q24h5mg/kg IV q24h, or half of regular dose q24h

General Information

Therapy for herpesviral infections (HSV and VZV) including encephalitis.

Prophylaxis of herpesviral infections if recurrent disease or immunocompromised.

Follow SCr as appropriate.

Check urine for crystals if AKI suspected.

  • ¬†GI upset

  • ¬†Phlebitis

  • ¬†Increased SCr

  • ¬†AKI from crystal nephropathy

Mycophenolate can increase the acyclovir concentration.

May diminish efficacy of zoster or varicella vaccine.

For oral indications, valacyclovir is the pro-drug, which is more bioavailable with more convenient dosing.

IV Administration
Give over at least 60 min in D5W or NS; maximum concentration 10 mg/mL

EH Prescribing Restrictions

Community IV Formulary (Metro Area)

No prescribing restrictions

Antimicrobial class: Antiviral. Nucleoside analogue.

Pregnancy category: B

Average serum half life: 3 hours

CSF penetration: Therapeutic

Urine penetration: Therapeutic