Description
Indications of Novirax 400
Novirax 400 applies to
- Treatment of viral infections caused by herpes simplex virus (types I and II) and varicella zoster virus (herpes zoster and chickenpox).
- Treatment of herpes simplex virus infections of the skin and mucous membranes, including early and recurrent genital herpes and herpes labialis.
- Prevention of herpes simplex infection in immunodeficiency patients
Pharmaceutical Name
Drug International Ltd
Pharmacology
Novirax 400 is a synthetic purine derivative. Aciclovir exerts antiviral activity against Herpes simplex virus (HSV) and Varicellazoster virus by interfering with DNA synthesis and inhibiting viral replication. In cells infected with herpes virus, the antiviral activity of aciclovir appears to depend mainly on the intracellular conversion of the drug to aciclovir triphosphate. Aciclovir is converted to aciclovir monophosphate primarily via the virus-encoded thymidine kinase; monophosphate is phosphorylated to diphosphate via cellular guanylate kinase, then via another cellular enzyme to triphosphate, which is the pharmacologically active form of the drug. 1530% of an oral dose of the drug is absorbed via the G1 route. Peak plasma concentrations usually occur within 1.52 hours after oral administration. It is widely distributed in body tissues and fluids, including brain, saliva, lung, liver, muscle, spleen, uterus, mucosal and vaginal fluids, CSF, and vesicular fluid. Aciclovir is excreted by the kidneys by glomerular filtration and tubular secretion
Dosage & Administration of Novirax 400
Treatment of initial herpes simplex: 200 mg 5 times daily usually for 5 days.
For immunocompromised patients:
- Adult: 400 mg 5 times daily for 5 days (longer if new lesions appear during treatment or if healing is incomplete; increase dose to 800 mg 5 times daily for genital herpes in immunocompromised) or as directed by the registered physician.
- Children under 2 years: Half of the adult dose.
- Children over 2 years: Adult dose.
Prevention of recurrence of herpes simplex:
- Adult: 200 mg 4 times daily or 400 mg twice daily possibly reduced to 200 mg 2 or 3 times daily and interrupted every 6-12 months.
- Children under 2 years: Half of the adult dose.
- Children over 2 years: Adult dose.
Prophylactic treatment of herpes simplex in the immunocompromised patients:
- Adult: 200 to 400 mg 4 times daily.
- Children under 2 years: Half of the adult dose.
- Children over 2 years: Adult dose.
Treatment of vericella (chicken pox):
- Adult and children over 40 kg: 800 mg 4 times daily for 5 days.
- Children below 40 kg: 20 mg/kg (maximum 800 mg) per dose orally 4 times daily (80 mg/kg/day) for 5 days.
- Children 1 month-2 years: 200 mg 4 times daily for 5 days.
- Children 2-5 years:400 mg 4 times daily for 5 days.
- Children 6-12 years:800 mg 4 times daily for 5 days.
Treatment of herpes zoster (Shingles): 800 mg 5 times daily for 7 days.
Treatment of initial rectal (Proctitis) herpes infections: An oral Aciclovir dosage of 400 mg 5 times daily for 10 days or until clinical resolution occurs has been recommended.
Renal Impairment: For patients with severe renal impairment, a reduction of the doses is recommended.
Interactions of Novirax 400
Probenecid reduces Aciclovir excretion and so increases plasma concentration and risk of toxicity.
Contraindications
Aciclovir is contraindicated in patients known to be hypersensitive to Aciclovir.
Side Effects of Novirax 400
Rash, digestive disorders, increased bilirubin and liver enzymes, increased blood urea and creatinine, decreased hematological indicators, headache, neurological reactions, fatigue.
Pregnancy & Lactation
Pregnancy category B. Acyclovir should not be used during pregnancy unless the potential benefit justifies the potential risk to the fetus. Caution should be taken when administering to breastfeeding mothers.
Precautions & Warnings
This drug should be given with caution in patients with renal impairment and should be dose-adjusted according to creatinine clearance. For newborns, monitor the number of neutrophils at least twice a week.
Therapeutic Class
Herpes simplex & Varicella-zoster virus infections
Storage Conditions
Should be stored below 25°C. It should be protected from light and moisture.Keep out of the reach of children.
