Spectrum: Local Antimicrobial Stewardship, for Billings Clinic

Acyclovir

C. diff Risk

None

Oral Bioavailability

Moderate

Approximate Cost

Oral: $
IV:$$

Spectrum Of Activity

General Spectrum of Activity

Spectrum Of Activity

Dosing

Renal

Pediatric

Adult

Serious Infections

  • e.g. CNS and Disseminated Zoster

  • 10mg/kg IV q8h

  • Use adjusted body weight for obese patients

Shingles

  • 800mg PO 5 times per day

  • Use valacyclovir instead

Prophylaxis and HSV mucocutaneous dosing varies by indication

  • Commonly used dose for mucocutaneous HSV: 400 mg PO TID

  • Commonly used dose for prophylaxis: 400-800 mg PO BID

General Information

Common Usage

Common Usage

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

Prophylaxis of herpesviral infections if recurrent disease or immunocompromised.

Drug Monitoring

Drug Monitoring

Follow SCr as appropriate.

Check urine for crystals if AKI suspected.

First Line Indications

First Line Indications

HSV encephalitis

Adverse Effects

Adverse Effects

  •  GI upset

  •  Phlebitis

  •  Increased SCr

  •  AKI from crystal nephropathy

Major Interactions

Major Interactions

Mycophenolate can increase the acyclovir concentration.

May diminish efficacy of zoster live or varicella vaccine.

Additional Information

Additional Information

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

Pharmacology

Pharmacology

Antimicrobial class: Antiviral. Nucleoside analogue.

Pregnancy category: B

Average serum half life: 3 hours

CSF penetration: Therapeutic with IV formulation

Urine penetration: Therapeutic