acyclovir, Zovirax (cont.)

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STORAGE: Acyclovir should be stored at room temperature, between 15 C 25 C (59 F to 77 F).

PRESCRIBED FOR: Oral acyclovir is used for treating genital herpes, shingles, and chickenpox.

Acyclovir reduces the pain and the number of lesions in the initial case of genital herpes, and decreases the frequency and severity of recurrent infections.

In the treatment of shingles, acyclovir reduces pain, shortens the healing time, and limits the spread of virus and the formation of new lesions.

Acyclovir can be used to treat chickenpox and acts to reduce healing time, limit the number of lesions, and reduce fever if used within the first 24 hours after the onset of illness.

Intravenous acyclovir is used for treating herpes simplex and chickenpox in immuno-compromised patients and severe genital herpes.

Acyclovir ointment is used topically to treat initial genital herpes where it has been shown to decrease pain, reduce healing time, and limit the spread of the infection.

DOSING: Acyclovir may be taken with or without food.

  • Adult oral doses for treating genital herpes are 200 mg every 4 hours (5 times daily) for 7-10 days or 400 mg three times daily for 5-10 days.
  • Herpes Zoster (shingles) is treated with 800 mg every 4 hours (5 times daily) for 7 to 10 days.
  • The dose for treating chicken pox is 800 mg 4 times daily. The usual adult intravenous dose is 5-10 mg/kg every 8 hours for 7-10 days.

DRUG INTERACTIONS: Acyclovir may decrease levels of phenytoin (Dilantin) or valproic acid (Depakote, Depakote ER). Probenecid (Benemid) may increase acyclovir serum levels by decreasing renal excretion of acyclovir. Acyclovir may increase serum levels of theophylline (Theo-Dur, Respbid, Slo-Bid, Theo-24, Theolair, Uniphyl, Slo-Phyllin).

Combining acyclovir with cidofovir (Vistide), amphotericin B (Fungizone) or other drugs that reduce kidney function may increase harmful effects on the kidney.

PREGNANCY: There are no adequate studies of acyclovir in pregnant women. In a patient registry of women who used acyclovir during the first trimester, the rate of birth defects was similar to the rate of birth defects in the general population.

Medically Reviewed by a Doctor on 7/24/2014


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