Acyclovir (Zovirax) 400 mg Tablet is a nucleoside analog antiviral agent that is indicated to treat herpes zoster, genital herpes, and chickenpox. Each tablet contains 400 mg of Acyclovir as its active ingredient.
Acyclovir demonstrates in vitro and in vivo inhibitory action against human herpesviruses. Acyclovir is converted to monophosphate acyclovir which is then transformed by cellular enzymes to diphosphate and eventually to triphosphate. Upon its penetration into the viral DNA, acyclovir triphosphate prevents viral DNA polymerase and replication of viral DNA.
Drug = Acyclovir
Strength = 400 mg
Contains = 50 tablets per order
How To Take
This medicine may be taken with or without food. It may be taken with meals to reduce gastrointestinal discomfort.
Try to take it at the same time each day. It must be taken regularly for it to be effective.
Take exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor. Do not stop taking it unless instructed by the doctor.
Dosage of Acyclovir (Zovirax) 400 mg
For treatment of herpes simplex: 200 mg 5 times daily at approximately every 4 hours intervals (omit night time dose) for five days.
Suppression of herpes simplex infections:
Immunocompetent patient: 200 mg four times a day at approximately every 6-hours intervals or 400 mg twice a day at approximately every 12-hours intervals. May titrate dose to 200 mg three times a day at approximately every 8-hours intervals or 200 mg twice a day at approximately every 12-hours intervals. Periodically interrupt therapy at 6-12 months intervals.
Prophylaxis of herpes simplex in immunocompromised patients: 200 mg four times a day at approximately every 6-hours intervals.
Severely immunocompromised patient (after marrow transplant) or those with impaired gut absorption: Double the dose to 400 mg four times a day.
Treatment of varicella & herpes zoster: 800 mg five times daily at approximately every 4-hours intervals (omit nighttime dose) for seven days.
Management of severely immunocompromised patients: 800 mg four times a day at approximately every 60-hours intervals.
If you often forget to take your medicine, let your doctor and pharmacist know.
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your usual dosing schedule.
Do not double a dose under any circumstances.
If you think you may have used Acyclovir more than the usual dose, please immediately seek medical help.
Symptoms of overdose may include the following:
People with the following medical conditions should not take Acyclovir:
- Hypersensitivity to acyclovir or valacyclovir
Acyclovir may have the following side effects:
- Abdominal pain
Warnings of Acyclovir (Zovirax) 400 mg
Do not take Acyclovir with the following medicines:
- Mycophenolate mofetil
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicine, supplements, and medicines that you buy without a prescription.
This list does not include all medicines that may interact with Acyclovir.
How Does It Work?
Acyclovir exhibits inhibitory activity against human herpesviruses in vitro and in vivo. Acyclovir is converted to acyclovir monophosphate, which is further converted to the diphosphate and finally to the triphosphate by cellular enzymes. Acyclovir triphosphate inhibits the viral DNA polymerase and viral DNA replication following its incorporation into the viral DNA.
Acyclovir is used to treat the following conditions:
- Treatment of herpes simplex virus infections of the skin and mucous membranes
- Initial and recurrent genital herpes
- Prevention of recurrent herpes simplex infections in immune-competent patients
- Prophylaxis of herpes simplex infections in immune-compromised patients
- Treatment of varicella infections (chicken-pox) & herpes zoster (shingles)
- Management of certain severely immunocompromised patients, with advanced HIV disease or following bone marrow transplantation
- Prophylaxis for herpes virus disease
Special Precautions and Connected Warnings
Take special precautions if you have the following conditions:
- Renal impairment
- Maintain adequate hydration in high-dose therapy
- Store at temperatures not exceeding 30°C.
- Store in a cool, dry place away from the reach of children.
- Do not use Acyclovir that is expired or out of date.