After oral administration, famciclovir is rapidly and almost completely absorbed and converted to the active penciclovir. Bioavailability penciclovir – 77%. Increased plasma concentration of penciclovir takes place proportionally to the single dose of famciclovir in the range 125-1000 mg. The maximum concentration testosterone enanthate cycle after oral administration of penciclovir 125 mg, 250 mg or 500 mg of famciclovir is achieved on average after 45 minutes , respectively. Other studies show penciclovir after ingestion of famciclovirl, respectively.
Systemic bioavailability penciclovir does not depend on the time of ingestion. Penciclovir at single dose of famciclovir, and the separation of the daily dose of famciclovir into two or three doses are similar to each other, suggesting no accumulation of penciclovir on repeated applications of famciclovir.
Linking blood plasma proteins penciclovir and its 6-deoxy precursor is less than 20%.
Famciclovir is displayed mainly in the form of penciclovir and its 6-deoxy precursor, which are excreted in the urine in unchanged form. Famciclovir in the urine can not be detected. Theof penciclovir from blood plasma at a final stage after a single dose and multiple dose of famciclovir is about 2 hours. Pharmacokinetics in special cases, patients with infections caused by zoster virus Varicella, revealed no significant changes in the pharmacokinetic parameters of penciclovir. Testosterone enanthate cyclein the final phase of penciclovir after single and repeated dosing of famciclovir was 2.8 and 2.7 hours, respectively.Patients with renal insufficiency In patients with renal failure after single and repeated dosing of famciclovir observed a linear relationship between the reduction in plasma clearance, renal clearance, clearance rate from plasma penciclovir and severity of renal insufficiency. The pharmacokinetic characteristics of the use of famciclovir in patients with severe (decompensated) renal impairment have not been studied. Patients with impaired liver function in patients with mild hepatic impairment and AUC of medium gravity function does not change. The pharmacokinetics of penciclovir in patients with severe hepatic impairment has not been studied. We can not exclude the possibility of breaking the transformation process into the active metabolite of famciclovir penciclovir in this group of patients, which may be accompanied by a reduction in plasma concentration of penciclovir and the resulting reduction in the efficiency of famciclovir. Elderly patients (over 65 years) patients aged 65-70 years marked increase in mean testosterone enanthate cycle penciclovir about 40% and reduced renal clearance penciclovir by approximately 20% compared to patients younger than 65 years old, which may partly be due to age-related changes in renal function in patients older than 65 years. The pharmacokinetic characteristics associated with the hollow floor the patient has no significant effect on the pharmacokinetic parameters of famciclovir (penciclovir clearance minor differences in men and women). The pharmacokinetic characteristics associated with racial When using famciclovir (single or multiple dosing of 500 mg of 1,2 or 3 times a day) in healthy volunteers blacks and blacks patients with impaired renal or hepatic function has not been found differences pharmacokinetic parameters compared with the use of famciclovir in similar groups of Caucasian patients.
- Infections caused by virus Varicella-zoster (shingles), including ophthalmoherpes; to reduce the risk of occurrence and duration of postherpetic neuralgia.
- Infections caused by viruses Herpes simplex 1 st, 2 nd type, including primary and recurrent infection (treatment of the primary infection, treatment and prevention of exacerbation of chronic infection).
- Infections caused by viruses Varicella-zoster and Herpes simplex 1 st, 2 nd type (labial and genital herpes), in patients with reduced immunity.Contraindications
: Hypersensitivity to famciclovir, penciclovir or to any component of the drug, children under 18 years (due to lack of efficacy and safety data).Precautions
Renal failure, severe (decompensated) liver dysfunction (no experience with).
Application of pregnancy and breastfeeding period
Experimental studies showed no embryotoxic and teratogenic effects of famciclovir and penciclovir.
In experimental studies, the application of famciclovir was noted inside the selection of penciclovir in breast milk. It is not known whether penciclovir in breast milk of women stands out.
However, since the safety of famciclovir in pregnant and lactating women has not been established, its use in pregnancy and lactation is possible only if the benefit of treatment to the mother outweighs the potential risk to the fetus and infant .
Dosing and Administration
Inside, regardless of meals, not liquid, squeezed water. Treatment should begin as soon as possible, immediately after the appearance of the first symptoms of the disease. Adult Infections. caused by virus Varicella-zoster (shingles), patients with normal immune status recommended dose – 500 mg 3 times a day for 7 days. Such method of use can reduce the duration of postherpetic neuralgia. In the acute phase of the disease to resolve cutaneous manifestations recommended dosage is 250 mg three times daily or 500 mg two times a day or 750 mg 1 time per day for 7 days. The recommended dose – 500 mg three times a day for 7 days. Infections caused by a virus Varicella-zoster (shingles) in patients with reduced immunity recommended dose – 500 mg 3 times a day for 10 days. Infections. caused by the virus Herpes simplex (labial and genital herpes) in patients with normal immunity
- Primary infection with genital herpes: The recommended dose – 250 mg 3 times a day for 5 days;
- with recurrent genital herpes: 1000 mg2 times a day for 1 day or 125 mg two times a day for 5 days or 500 mg dose, followed by application of 3 doses of 250 mg every 12 hours;
- with recurrent herpes labialis: 1500 mg once daily for 1 day or 750 mg 2 times a day for 1 day. Infections caused by virus Herpes simplex (labial and genital herpes) in patients with reduced immunityrecommended dose – 500 mg 2 times per day for 7 days. For the prevention of recurrent exacerbations of infection by the virus Herpes simplex (suppressive therapy) – 250 mg 2 times a day. The duration of therapy depends on the severity of the disease.
- The effectiveness of a one-day admission to the dose of 1000 mg 2 times a day for treatment of recurrent genital herpes in immunocompetent patients blacks are not greater than that for placebo. The clinical relevance of the dosing regimes as a treatment for genital herpes recurrences (within 2 or 5 days), and other infectious diseases caused by virusVaricella-zoster and Herpes simplex 1 st, 2 nd type is unknown.Side effects:
The frequency of side effects is classified according to the following criteria: very often – at least 10%; often – at least 1% and less than 10%; sometimes – not less than 0.1% and less than 1%; rare – less than 0.01% and less than 0.1%; very rarely – less than 0.01%, including isolated reports. Blood system and blood-forming organs: rarely – thrombocytopenia. From the nervous system: very often – headache;often – dizziness; rare – confusion (predominantly in elderly patients), somnolence (predominantly in the elderly); rarely – hallucinations. On the part of the gastrointestinal tract: often – nausea, vomiting, diarrhea, abdominal pain. Liver and biliary tract: often – increased concentration of bilirubin and activity of “liver” transaminases; . rarely – cholestatic jaundice Allergic reactions: often – skin rash, itching; rarely – angioedema (swelling of the face, eyelids, periorbital region, throat), urticaria; unknown frequency – severe skin reactions: erythema multiforme, Stevens-Johnson syndrome, Lyell’s syndrome (toxic epidermal necrolysis). From testosterone enanthate cycle the musculoskeletal system: very rarely – myalgia, arthralgia. From the urinary system: rarely – hypercalcemia, QC change; very rarely – gemalitiko-uremic syndrome (with high doses of famciclovir in patients with lowered immunity). Other: often – increased sweating; very rare – fever.
There are limited data on overdose of famciclovir. Treatment: symptomatic and supportive. Failure to comply with the recommendations to reduce the dose of famciclovir in view of kidney function in patients with kidney disease is rarely observed cases of acute renal failure. Penciclovir, which is the active metabolite of famciclovir, appear in hemodialysis. Pentsilovira concentration in blood plasma is reduced by 75% after dialysis for 4 hours.