Valtrex pills 500mg №42

Active ingredient

Valtrex pills: 1 pill Valtrex contains Valaciclovir 500 mg;
Excipients: microcrystalline cellulose, crospovidone, povidone K90, Magnesium stearate, anhydrous colloidal silicon, carnauba wax, white dye concentrate, printing ink containing diamond blue 5312 (FT 203).
10 or 42 pcs. packaged.

Mechanism of action

 
Valtrex is an antiviral drug. It is a specific inhibitor of the DNA polymerase of the herpes virus. Blocks viral DNA synthesis and virus replication. 
In humans, valaciclovir is converted to Acyclovir and valine. As a result of phosphorylation from acyclovir, active acyclovir triphosphate is formed, which competitively inhibits viral DNA polymerase. The first stage of phosphorylation occurs under the influence of a virus-specific enzyme. For the viruses Herpes simplex, Varicella zoster and Epstein-Barr, this enzyme is viral thymidine kinase, which is found only in cells infected with the virus. For cytomegalovirus, drug selectivity is due to the fact that phosphorylation, at least partially, is mediated by the UL97 phosphotransferase gene product. The need for a virus-specific enzyme to activate acyclovir largely explains its selectivity. 
In vitro Valacyclovir is active against Herpes simplex types 1 and 2 viruses, Varicella zoster and Epstein-Barr viruses, cytomegalovirus and human herpes virus type 6. 
Extensive study of clinical strains isolated from patients has shown that in patients with normal immunity, viruses with reduced sensitivity to acyclovir are extremely rare. Somewhat more often or relatively rarely, these viruses are detected in individuals with marked immunodeficiency, for example, recipients of internal organs or bone marrow; in patients receiving Chemotherapy for malignant neoplasms, and people infected with HIV. The reduced sensitivity of viruses to acyclovir is due to the phenotypic deficiency of thymidine kinase in cells infected with the virus. Less commonly, the cause of reduced sensitivity to acyclovir was hidden changes in viral thymidine kinase or DNA polymerase.

Treatment of herpes zoster; 
Treatment of diseases of the skin and mucous membranes caused by the Herpes simplex virus types 1 and 2 (including the first identified and recurrent genital herpes); 
Prevention of recurrence of diseases of the skin and mucous membranes caused by the Herpes simplex virus types 1 and 2 (including genital herpes); 
Prevention of cytomegalovirus infection and diseases developing after organ transplantation. Prevention with Valtrex reduces the graft rejection reaction, the development of infections caused by conditionally pathogenic microorganisms, and other viral infections (including herpes zoster).

Dosage and administration

 
Inside (regardless of the meal).The dosing regimen is set individually, depending on the evidence. It is recommended to start therapy as early as possible, the greatest effectiveness is noted if treatment was started within 48 hours from the first appearance of signs or symptoms of the disease (rash, pain or a burning sensation).

For the treatment of herpes zoster appoint 1 g of Valtrex 3 times / day for 7 days.

For the treatment of diseases caused by Herpes simplexValtrex is prescribed 500 mg 2 times / day.

With the recurrence of diseases caused by the virus Herpes simplex, treatment is best to start in the prodromal period or immediately after the first symptoms appear. The duration of treatment is 3-5 days. In the first episode, which may be more severe, the duration of treatment can be increased up to 10 days, and Valtrex should be prescribed as soon as possible.

For the prevention of recurrence of diseases caused by the virus Herpes simplex, adults with normal immunity indicators Valtrex appoint 500 mg 1 time / day. With very frequent exacerbations (10 or more times a year), it may be more effective to administer 250 mg 2 times / day. Adults with immunodeficiency appoint 500 mg of Valtrex 2 times / day.

For the prevention of cytomegalovirus infection adults and adolescents over 12 years old dose is 2 g 4 times / day. Valtrex is prescribed as soon as possible after transplantation. Dose can be changed according to creatinine clearance. The duration of the course is usually 90 days, but can be increased in patients with a high risk of developing infections.

Patients with impaired renal function dosing regimen is set depending on creatinine clearance.

In renal failure patients on hemodialysis, Valtrex should be prescribed in the dose recommended for patients with CC less than 15 ml / min. Valtrex should be used after hemodialysis.

Patients with impaired mild or moderate liver function do not require dose adjustment. In the study of pharmacokinetics in patients with severe cirrhosis of the liver and impaired synthetic liver function, no data have been obtained indicating that the dosage regimen must be adjusted; however, clinical experience with the use of the drug Valtrex in this category of patients is organic.

Adverse reactions

 
Gastrointestinal: nausea, vomiting, diarrhea, discomfort; rarely, transient increases in liver function tests. 
From the side of the central nervous system: rarely - headache; very rarely, reversible neurological disorders, such as dizziness, confusion, hallucinations (usually in patients with impaired renal function or other predisposing factors). 
Allergic reactions: rarely - rash, urticaria, pruritus, angioedema, anaphylaxis. 
Other: rarely - thrombocytopenia, shortness of breath, renal dysfunction.

In patients with severe immunodeficiency who received valacyclovir in high doses (8 g / day) for a long time, cases of development of renal failure, microangiopathic hemolytic anemia and thrombocytopenia (sometimes in combination with each other) are described.It should be noted that to date, the relationship between the development of the described side reactions and the use of valacyclovir has not been completely established.

Contraindications

 
Hypersensitivity to valacyclovir, acyclovir.

Pregnancy and breastfeeding

 
There are limited data on the use of Valtrex during pregnancy. Valtrex is used only in cases where the potential benefit to the mother outweighs the possible risk to the fetus. 
It is recommended to use caution when prescribing Valtrex during lactation.

Special notes

 
Elderly patients during the period of treatment with Valtrex need to increase the amount of fluid consumed. 
Experience with the clinical use of the drug Valtrex in children is absent.

 
Store Valtrex at temperatures not exceeding 30 ° C. 
Shelf life - 3 years.