Acyclovir
Adult

Adult

Use actual body weight to calculate weight-based dosing. Follow obesity dosing below if:

  • Actual body weight is 30% or more above IBW OR
  • BMI equal to or greater than 30 kg/m2

HSV:

Genital (primary or nonprimary episode):
200 mg PO 5 times per day x 5-10 days

Recurrent Genital Lesions:
200 mg PO 5 times per day x 5 days
OR
800 mg PO TID x 2 days
Initiate at onset of symptoms

Herpes labialis:
200-400 mg PO 5 times per day x 5 days

Unable to take oral or severe mucocutaneous infection: 5 mg/kg IV Q8H
(Switch to oral once improved).

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

VZV/Zoster:

Chicken Pox in Adulthood:
800mg PO QID x 5 days

Shingles:
800 mg 5 times per day x 7-10 days

Serious Infections
(e.g. CNS and Disseminated)
10-15 mg/kg IV q8h (higher doses typically reserved in HIV/immune compromise - see full guidelines or consult ID for details)

Prophylaxis dosing varies by indication refer to specific treatment guidelines.

See Canadian Guidelines on Sexually Transmitted Infections for full management recommendations for HSV.

Obesity

Use adjusted body weight (ABW) for patients with obesity (weight is 30% or more above IBW or BMI 30 kg/m2 and above) in order to avoid overdosing and potential toxicity.

 ABW = (IBW + 0.4x[TBW-IBW])