Zovirax

Zovirax has antiviral properties.

Indications of the zovirax

Tablets are used for such violations:

• elimination of infections provoked by the activity of the chickenpox virus and herpes zoster;
• treatment of infections that occur in the mucous and skin, HSV of any kind (this includes genital herpes, having a primary or recurrent form);
• preventing the development of recurrences of HSV infections of any type in people with healthy immunity or with the presence of immunodeficiency;
• treatment of people with immunodeficiency severely (often HIV infection with CD4 + below 200 cells / mm3 and early symptoms of HIV, as well as clinical manifestations of AIDS ) or after bone marrow transplantation.

Use of the drug in the ointment form is carried out with keratitis caused by HSV of any type.

The cream is prescribed for the elimination of HSV infections of any kind occurring on the mucous and dermal surface (this includes herpes in the lips area).

Use of liquid for injection:

• treatment of HSV infections of any variety;
• prevention of the development of infections of any kind of HSV on mucous membranes or skin surface in people with immunodeficiency;
• elimination of infections caused by the varicella-zoster virus;
• treatment of HSV infections of any form in newborn infants;
• preventing the development of CMV after the procedure of bone marrow transplantation.

Release form

Release of the medicine occurs in several forms:

• tablets, 5 pieces inside a blister plate, 5 plates each inside the pack;
• 5% cream applied externally - in plastic bottles with a capacity of 2 g, equipped with a dispenser. Inside the box there is one such bottle. Also produced in tubes with a volume of 2, 5 or 10 g, 1 tube per package;
• Ointment in a tube with a capacity of 4.5 grams, having a plastic nozzle. Inside the pack - 1 such a tube;
• injection lyophilizate - in flakonchikah of glass capacity of 0.25 g. Inside the blister pack - 5 of these vials. The box contains 1 such package.

[1], [2],

Pharmacodynamics

An antiviral agent, a synthetic analogue of a purine nucleoside, which has the ability to slow down viral replication of any type of HSV, CMV, Varicella zoster, and in addition VEB. Acyclovir substance has a powerful antiviral effect against the herpes simplex virus type 1.

The activity of the drug against viruses is highly selective. Thymidine kinase of those cells that are affected by the viruses described above, converts the molecules of the active element of the drug into monophosphate, and then sequentially into 2-phosphate and 3-phosphate (under the influence of cellular enzymes). Due to the inclusion of the 3-phosphate of the active element in the viral DNA chain with further rupture of this chain, the copy of pathogenic DNA is blocked.

In individuals with immunodeficiency in severe form, prolonged or repeated courses of therapy with acyclovir may cause the development of drug-resistant strains. Also, in a variety of strains with low sensitivity to Zovirax, low values of thymidine kinase of the virus were observed.

[3], [4], [5], [6]

Pharmacokinetics

Pharmacokinetic properties of injections and tablets.

After applying the inside, the active element is only partially absorbed from the digestive tract. The level of matter inside the liquor is about half of its values inside the plasma. Only a small part of the drug is synthesized with blood protein (10-33%).

The main product of metabolism is the substance 9-carboxymethoxy-methylguanine. The half-life is 2.7-3.3 hours. The main part of the medicine is excreted in the form of an unchanged element through the kidneys. This is due to the processes of glomerular filtration and tubular secretion.

In people with chronic kidney failure, the half-life of the drug is approximately 19.5 hours. In elderly people, the drug clearance rate decreases with age, but changes in the half-life are almost invisible.

Pharmacokinetic characteristics of the ointment.

After using the ointment, the active element is rapidly absorbed through the corneal epithelium and the tissue around the eyes, resulting in the formation of the therapeutic concentration required to suppress the activity of the virus in the intraocular fluid.

In this method of use, acyclovir is found inside the urine in extremely low concentrations that do not have a medicinal value.

[7], [8], [9], [10], [11],

Dosing and administration

Scheme for the use of medication tablets.

Take the tablets inside, along with food, washing down with plain water (0.2 liters).

To eliminate infections associated with HSV, you need to take 0.2 g LS at intervals of 4 hours, 5 times / day. The treatment course usually lasts 5 days, but with the treatment of severe illness it can be prolonged. If the patient has a marked degree of immunodeficiency or a violation of intestinal absorption of drugs, the size of his portion can be increased to 0.4 g while maintaining the above frequency of use. It is recommended to begin therapy as soon as possible after the infection. In case of recurrence of the disease, the drug is taken immediately after the appearance of the first signs.

To prevent the recurrence of infections associated with HSV in people with a healthy immune system, you should use four times a day for 0.2 grams of medication, observing the same time intervals between doses. There is also an option with a more convenient mode of use - 0.4 g twice a day. Sometimes, small portions of drugs - 0.2 g 2-3 times / day - show higher efficacy. To prevent infection in some patients it is possible only after taking a total daily dose of 0.8 g.

Treatment should be stopped periodically (intervals of 0.5-1 year) to determine the presence of changes in the course of the disease.

In the prevention of the development of recurrences of infections associated with HSV, in people with immunodeficiency, it is required to take four times a day for 0.2 g of drugs. People with a significant degree of immunodeficiency or a violation of intestinal absorption are allowed to increase the size of the portion to 0.4 g, which are taken five times a day. The period of preventive therapy is chosen taking into account the duration of the infectious dangerous interval.

For the treatment of herpes zoster, as well as chickenpox it is necessary to take 0.8 grams of medication five times a day (excluding the period of night sleep). Such therapy lasts 7 days. It should be prescribed as soon as possible after the infection, in order to increase the effectiveness of treatment.

In the treatment of patients with immunodeficiency, 0.8 g of Zovirax is prescribed in a severe manner four times per day (with the same time intervals between doses). People who have undergone a bone marrow transplant operation before oral administration of the drug often require a 1-month course with a parenteral route of administration of the drug. Treatment in people who have been transplanted bone marrow, lasts no more than 0.5 years. In people with a developed clinical picture of HIV, the duration of therapy was 12 months.

People with kidney failure in severe extent, the size of portions of Zovirax should be reduced to 0.2 g with twice daily use.

When eliminating chickenpox or herpes zoster, and in addition to this therapy in people with severe immunodeficiency, the sizes of the standard portions are:

• at the expressed stage of a failure of kidneys - 0,8 g twice a day;
• with a moderate degree of kidney failure - 0.8 g three times a day.

The mechanism of ointment for the eyes.

A strip of ointment with a length of 10 mm should be placed in the area of the conjunctival sac. The procedure is carried out a maximum of 5 times / day. After eliminating the symptoms of the disease should continue to therapy for at least another 3 days.

Diagram of the use of the cream.

Apply the cream with a cotton swab, or with clean hands - to prevent the reinfection of affected areas.

A small amount of the drug must be applied to the affected areas, as well as to the skin / mucous near them. The procedure is performed up to 5 times / day.

The duration of therapy is usually 4 days. If the wound does not heal, the treatment can be extended up to 10 days. If there is no result after 10 days of therapy, consult your doctor.

Mode of use of injection lyophilizate.

The ready-made solution must be administered intravenously. People suffering from obesity are given the same portions of medicines as those with a healthy weight.

When eliminating infections caused by the activity of HSV, as well as herpes zoster virus, the medication is administered in / in the way in a dose of 5 mg / kg, three times a day.

When treating infections associated with herpetic character encephalitis or herpes zoster, people with immunodeficiency require an intravenous injection of 10 mg / kg three times a day.

To prevent the development of CMVI after bone marrow transplantation, the drug is injected / in the method in a dose of 0.5 mg / m ², three times a day. Treatment begins on the 5th day before the transplant procedure, and then it lasts until the 30th day after it.

It is necessary to carefully select the dosage for elderly people with lower QC values - the introduction of reduced portions is required.

People with kidney failure need to carefully prescribe intravenous injection Zoviraksa. Changing the size of portions is necessary in view of the severity of the disease.

Infusion therapy usually lasts 5 days, although the course may vary depending on the patient's response to treatment, as well as his condition. The sizes of the preventive period are selected depending on the duration of the infectious-dangerous gap.

Production of a medicinal liquid and methods of administration.

The drug is injected / in a method at a slow speed. The duration of the procedure is more than 60 minutes.

To make a solution, the concentration of the active element in which is 25 mg / ml, it is required to add 10 ml of usual water or saline solution inside the ampoule with lyophilizate, then gently shake it until the contents completely dissolve.

Another method of preparing the infusion may be used: the final solution is diluted to a concentration of 5 mg / ml (while the finished infusion fluid must be added to one of the solutions, and then shaken so that these solutions completely mix). Adults should be given infusions in packets of 0.1 liters, despite the diluted acyclovir, which is less than 0.5%.

For IV injections, the drug can be combined with such solutions (the drug will remain stable for 12 hours at temperatures in the range of 15-24 ° C):

• 0.18% NaCl solution and 4% glucose solution;
• 0.45% NaCl solution and 2.5% glucose solution;
• 0.45% or 0.9% NaCl solution;
• Hartman solution.

Application for children

Use of tablets.

When eliminating and preventing diseases caused by HSV, in children who suffer from immunodeficiency:

• Infants up to 2 years of age are prescribed half of the adult portion;
• Children from 2 years old are required to take the medicine in the portions recommended for adults.

In the treatment of chickenpox, such dosage sizes are prescribed:

• Infants under 2 years of age are required to take 0.2 g of medicinal products four times a day;
• children in the age category 2-6 years should use 0.4 g of the drug four times a day;
• children from the age of 6 years old should use 0.8 grams of medication four times a day.

You can choose a more accurate portion size, guided by the weight of the child - 20 mg / kg four times a day. The duration of treatment is usually 5 days.

Use of injection lyophilizate.

The sizes of portions for IV injections for children aged 3 months to 12 years are determined by taking into account the size of the body area.

During the treatment of pathologies caused by the activity of HSV (except for herpes encephalitis), and in addition to herpes zoster virus, the size of IV infusions is selected from the calculation of 0.25 g / m ² three times a day.

When eliminating infections provoked by viral activity (herpes zoster, as well as herpes encephalitis), for children with immunodeficiency, dosages are selected according to the scheme 0.5 g / m ² three times a day.

For newborns, the portions are selected taking into account the indices of their weight.

To eliminate infections associated with HSV, in newborns - should choose the appropriate dosage according to the scheme of 10 mg / kg, with a triple application per day. Usually such treatment lasts 10 days.

[15], [16]

Use of the zovirax during pregnancy

Prescribing zovirax to pregnant or lactating women requires very careful, only if there is a medical indication and after a thorough assessment of the likelihood of use and risk for the woman and the child / fetus.

Tests did not find an increase in the number of congenital abnormalities in children whose mothers used medication during pregnancy, compared to children whose mothers did not use it.

Contraindications

The main contraindication is the intolerance of valaciclovir or acyclovir and other elements of the drug.

Intravenous injections are prohibited in such cases:

• dehydration;
• kidney failure;
• neurological disorders;
• negative reactions to intravenous injections of cytotoxic drugs (also their presence in the past).

Tablets are not allowed for dehydration and kidney failure.

[12], [13]

Side effects of the zovirax

When using powder or tablets, these side effects may appear:

• disorders of the digestive function: nausea, diarrhea, vomiting, and abdominal pain (when ingested);
• disorders in the hematopoietic system: anemia, thrombocyto- or leukopenia;
• manifestations of hypersensitivity: febrile state, angioedema, dyspnea, rashes, urticaria, anaphylaxis, pruritus, photosensitivity and severe inflammation in the parenteral site;
• Renal impairment: an increase in the values of urea and creatinine within the blood. To avoid such symptoms, instead of a quick IV injection, use an introduction at a lower speed (the procedure should last 60 minutes). Kidney failure caused by intravenous drug injections is often eliminated by reducing the dose of the drug or by performing a rehydration procedure;
• hepatic disorders: a transient increase in liver enzymes and bilirubin, as well as the development of hepatitis or jaundice (occasionally, after parenteral administration);
• lesions affecting the function of the NS: sensation of drowsiness, confusion, as well as nervous excitement. In addition, the development of convulsions, psychosis, hallucinations, tremors, coma and headaches (when ingested);
• Other disorders: alopecia and a state of severe fatigue.

Disorders caused by the use of ophthalmic ointment:

• Immune disorders: manifestations of intolerance that can reach the edema of Quincke;
• visual disorders: conjunctivitis, mild transitory burning, blepharitis, as well as keratopathy of a point character (disappears without complications, it is not necessary to cancel therapy for this).

Negative signs that appear after applying the cream:

• local symptoms: transient itching, burning sensation, redness, peeling, and tingling at the treatment site;
• manifestations of allergy: angioedema, and dermatitis.

[14]

Overdose

Poisoning with pills.

In the case of a one-time accidental ingestion of portions of drugs to 20 g of development, no side effects are noted.

Among the symptoms of an overdose: vomiting, diarrhea, headaches, nausea, dyspnea and a sense of confusion. In addition to this, cramps, functional renal impairment, coma and lethargy.

It is necessary to carefully monitor the patient in order to determine the symptoms of poisoning in a timely manner. The procedure of hemodialysis can be used.

Intoxication with solution.

Symptoms of poisoning: the development of kidney failure, convulsions, coma, feelings of excitement or confusion, as well as hallucinations. In addition, there is an increase in the creatinine and urea nitrogen levels in the blood.

To eliminate the disorder requires the procedure of hemodialysis, because it significantly increases the excretion of acyclovir from the body. Due to this, this procedure is considered the best method of treatment in case of intoxication with Zoviraks solution.

[17], [18], [19]

Interactions with other drugs

Unchanged acyclovir enters the urine with the secretion of tubules, so all drugs that have a similar method of excretion can increase the values of acyclovir within the blood.

It is necessary to carefully combine intravenous injection of Zovirax with medications that disrupt the renal function (such as tacrolimus, cyclosporine and others).

[20], [21], [22]

Storage conditions

Zovirax should be kept in a dry place, closed from the access of children. Temperature conditions are standard for medicines.

[23],

Shelf life

Zovirax can be used for 5 years from the date of manufacture of the therapeutic agent.

[24], [25]

Analogues

Analogues of the drug are such drugs: Acyclovir, Acyclovir-Acry, Acyclovir Belupo, as well as Acyclovir-Acrychin and Acyclovir Sandoz. In addition, the list includes Acigerpin, Aksikorstad, Gerperax with Vivorax and Medovor, and also Atsivir, Virolex, Zovirax Duo and Provirsan with Herpetad.

[26], [27], [28]

Reviews

Zovirax receives mostly positive reviews, which indicate a high drug effectiveness of the drug. Often it is used to treat herpes. In the reviews there are almost no reports of a lack of results after the use of drugs, as well as the development of side symptoms. The only drawback, according to patients, is the high cost of the drug.