Simplovir

Simplovir intravenous infusion is indicated for the treatment of-

Acute clinical manifestations of Herpes simplex virus in immunocompromised patients

Severe primary or non-primary genital herpes in immune competent patients

Varicella zoster virus infection in immunocompromised patients

Herpes zoster (shingles) in immune competent patients who show very severe acute local or systemic manifestations of the disease

Herpes simplex encephalitis

Acyclovir exerts its antiviral e­ects on Herpes simplex virus and Varicella zoster virus by interfering with DNA synthesis and inhibiting viral replication. In cells infected with Herpes virus, the antiviral activity of Acyclovir appears to depend principally on the intracellular conversion of the drug to Acyclovir Triphosphate. Acyclovir is converted to Acyclovir Monophosphate principally via virus coded thymidine kinase, the monophosphate is phosphorylated to diphosphate via cellular guanylate kinase and then via other cellular enzymes to the Triphosphate, which is the pharmacologically active form of the drug.

Herpes simplex infection: For normal or immunocompromised immune status: 5 mg/kg every 8 hours

Very severe Herpes zoster infection (shingles): For normal immune status: 5 mg/kg every 8 hours

Varicella zoster infection: For immunocompromised immune status: 10 mg/kg every 8 hours

Herpes simplex encephalitis: For normal or immunocompromised immune status: 10 mg/kg every 8 hours

Each dose should be administered by slow intravenous infusion over a one-hour period.

Co-administration of probenecid with Simplovir has been shown to increase the mean Simplovir half-life and the area under the concentration time curve. Urinary excretion and renal clearance correspondingly reduced. In patients over 60 years of age concurrent use of diuretics increases plasma levels of Simplovir very significantly.

Acyclovir IV Injection is contraindicated in patients known to be hypersensitive to Acyclovir or Valacyclovir.

Some infrequent adverse reactions are lethargy, obtundation, tremors, confusion, hallucinations, agitation, somnolence, psychosis, convulsions and coma, phlebitis, nausea, vomiting, reversible increases in liver-related enzymes, pruritus, urticaria, rashes, increases in blood urea and creatinine. Local inflammatory reactions may occur if Simplovir IV Infusion is inadvertently infused into extracellular tissues.

Pregnancy category B. There have been no adequate and well controlled studies concerning the safety of Acyclovir in pregnant women. It should not be used during pregnancy unless the benefits to the patient clearly outweigh the potential risks to the fetus. Acyclovir should only be administered to nursing mothers if the benefits to the mother outweigh the potential risks to the baby. There is no experience of the effect of Acyclovir on human fertility.

Simplovir IV injection is intended for intravenous infusion only and should not be used through any other route. Reconstituted Simplovir IV Infusion has a pH of approximately 11.0 and should not be administered by mouth. Simplovir IV injection as infusion must be given over a period of at least one hour in order to avoid renal tubular damage. It should not be administered as a bolus injection. Simplovir IV infusion must be accompanied by adequate hydration. Since maximum urine concentration occurs within the first few hours following infusion, particular attention should be given to establish sufficient urine ‑ow during that period. Concomitant use of other nephrotoxic drugs, pre-existing renal disease and dehydration increase the risk of further renal impairment by Simplovir. As Simplovir has been associated with reversible encephalopathic changes, it should be used with caution in patients with neurological abnormalities, significant hypoxia or serious renal, hepatic or electrolyte abnormalities.

Overdosage of intravenous Simplovir has resulted in elevations of serum creatinine, blood urea nitrogen and subsequent renal failure. Neurological effects including confusion, hallucinations, agitation, seizures and coma have been described in association with over dosage. Adequate hydration is essential to reduce the possibility of crystal formation in the urine. Hemodialysis significantly enhances the removal of Simplovir from the blood and may, therefore, be considered an option in the management of overdose of Simplovir.

Store at 15°C to 25°C. Protected from light and moisture. Keep the medicine out of the reach of children.