Virostat is a direct-acting antiviral agent.
Indications for use
Infections caused by the Varicella Zoster virus (VZV), or shingles:
- herpes zoster, including ocular herpes zoster in immunocompetent adult patients;
- Shingles in adult patients with weakened immunity.
Infections caused by the Herpes Simplex Virus (HSV) – genital herpes:
- treatment of the first manifestations and recurrences of infectious genital herpes in immunocompetent adult patients;
- treatment of recurrent genital herpes in adult patients with weakened immunity;
- Suppression of recurrent genital herpes in immunocompetent adult patients and in immunocompromised adult patients.
Composition
- active ingredient: famciclovir;
- 1 tablet contains famciclovir 250 mg;
- excipients: sodium starch glycolate (type A), hydroxypropyl cellulose, magnesium stearate; shell: Opadry White film coating mixture: hypromellose (hydroxypropyl methylcellulose), titanium dioxide, polyethylene glycol (macrogol).
Contraindication
Hypersensitivity to famciclovir or other components of the drug, as well as hypersensitivity to penciclovir.
Adverse reactions
Headache, nausea, diarrhea, and drowsiness have been reported in clinical studies.
From the side of the blood and lymphatic system: rarely – thrombocytopenia.
On the part of the psyche: uncommon – confusion (mainly in elderly patients); rare – hallucinations.
Central nervous system (CNS): very common – headache; common – dizziness; uncommon – drowsiness (predominantly in elderly patients); rare – convulsions*.
Cardiac disorders: rarely – increased heartbeat.
Gastrointestinal: common – nausea, vomiting, abdominal pain, diarrhea; rare – pancreatitis*.
Method of application
Since the systemic bioavailability of penciclovir was not altered when famciclovir was taken with food, famciclovir can be administered without regard to meals.
For the treatment of shingles – 500 mg 3 times a day for 7 days. For the treatment of shingles with eye complications – 500 mg 3 times a day for 7 days. Treatment gives better results if it is started immediately after the appearance of the rash.
Shingles in immunocompromised patients: 500 mg 3 times daily for 10 days. It is recommended to start treatment immediately after the appearance of the rash.
Genital herpes in immunocompetent patients:
- first manifestation of genital herpes: 250 mg 3 times a day for 5 days. It is recommended to start treatment immediately after the first manifestation of genital herpes;
- Recurrence of genital herpes: 125 mg twice daily for 5 days*. It is recommended to start treatment during the prodromal period (tingling sensation, itching, burning, pain) or immediately after the first manifestation of genital herpes.
Recurrence of genital herpes in immunocompromised patients: 500 mg 2 times a day for 7 days. It is recommended to start treatment in the prodromal period (tingling sensation, itching, burning, pain) or immediately after the appearance of rashes.
Application features
Use during pregnancy or breastfeeding
Pregnancy: Although animal studies have not shown any embryotoxic or teratogenic effects of famciclovir or penciclovir, the safety of famciclovir in pregnant women has not been established.
Lactation: Studies in rats have shown that penciclovir is excreted in the breast milk of dams given famciclovir orally. It is not known whether penciclovir is excreted in human milk. Therefore, famciclovir should be used during pregnancy or breastfeeding only if the expected benefit to the woman justifies the potential risk to the infant.
Children
The efficacy and safety of famciclovir in children and adolescents (under 18 years of age) have not been studied. Therefore, famciclovir is not used in patients in this age group.
Ability to influence reaction speed when driving vehicles or other mechanisms
There are no data on the impairment of patients’ ability to drive or operate machinery under the influence of famciclovir. However, patients who experience dizziness, drowsiness, confusion, or other central nervous system disorders while taking the drug should refrain from driving or operating machinery.
Overdose
Data on overdose with famciclovir are limited. Reports of accidental acute overdoses (10.5 g) are few. Long-term use (10 g per day for 2 years) of famciclovir did not cause complications. In case of overdose, supportive therapy should be used. Isolated cases of acute renal failure have been described in patients with a history of kidney disease in whom the dose of the drug was not reduced accordingly. The concentration of the drug is reduced by approximately 75% during 4 hours of hemodialysis.
Interaction with other medicinal products and other types of interactions
Probenecid and other drugs that affect renal physiology may alter the plasma levels of penciclovir (the active metabolite of famciclovir).
Therefore, patients receiving famciclovir 500 mg three times daily with probenecid should be monitored, particularly for toxicity. A dose reduction may be necessary for these patients.
Storage conditions
Store in the original packaging at a temperature not exceeding 25 °C.
Keep out of reach of children.







Reviews
There are no reviews yet.