Antiviral drug (virostatic), acyclic analogue of guanine, a natural component of DNA, synthetic analogue of thymidine nucleoside.
The enzyme thymidine kinase of virus-infected cells actively converts (phosphorylation) Acyclovir through a series of consecutive reactions to the active form - acyclovir triphosphate, which penetrates into the cell affected by the herpes virus, inhibits DNA polymerase and competitively replaces deoxyguanosine triphosphate in the synthesis of DNA viruses. Acyclovir triphosphate, "embedding" in the virus synthesized by the virus, blocks the reproduction of the virus.
High selectivity of action and low toxicity for humans are due to the lack of the necessary enzyme for its activation in intact cells of the macroorganism. The drug does not allow the possibility of its influence on the normal life processes occurring in the cell. The specificity and very high selectivity of action is also due to its predominant accumulation in cells affected by the herpes virus.
The drug is active against herpes simplex Herpes simplex types 1 and 2, the virus that causes varicella and shingles Varicella zoster, Epstein-Barr virus. It has a selectivity of action. Moderately active against cytomegalovirus.
When herpes prevents the formation of new elements of the rash, reduces the likelihood of skin dissemination and visceral complications, accelerates the formation of crusts, reduces pain in the acute phase of herpes zoster. It has an immunostimulating effect.
Indications and usage
Treatment of infections of the skin and mucous membranes caused by the Herpes simplex virus types 1 and 2, both primary and recurrent (including herpes lips, genital herpes, acute primary genital infections). Treatment of infections caused by Varicella zoster viruses (including chicken pox, shingles, and herpes zoster). Treatment and prevention of infections of the skin and mucous membranes caused by the Herpes simplex virus types 1 and 2 in immunodeficiency patients. Prevention of diseases caused by the Herpes simplex virus, after transplantation.
Systemic use (inside and in / in) - encephalitis, neonatal herpes infection, herpes eczema, pneumonia.
Outwardly - herpes simplex skin and mucous membranes, genital herpes (primary and recurrent); shingles, chicken pox.
Local - herpetic keratitis.
In case of infection of the skin and mucous membranes caused by the herpes simplex virus, cream or ointment (5%) is applied to the affected surface 5-6 times a day (every 3-4 hours) for 5-10 days.
For herpetic keratitis (eye ointment) - 5 times a day for 7-10 days.
Adults in the treatment of herpes simplex skin and mucous membranes, the drug is prescribed 200 mg 5 times / day every 4 hours, except during the night's sleep for 5 days (if necessary, it can be extended). Treatment begins in the prodromal period or when the first elements of the rash appear.
When treating patients with immunodeficiency (including after bone marrow transplantation or intestinal absorption), a single dose of the drug should be increased to 400 mg 5 times a day or administered intravenously 5 mg / kg 3 times a day with an interval 8 h. Treatment should begin as soon as possible after the occurrence of infection.
For the prevention of recurrence of herpes simplex, patients with a normal immune status are prescribed 200 mg 4 times a day every 6 hours or 400 mg 2 times a day every 12 hours.
For the prevention of herpes infections in patients with immunodeficiency, the drug is prescribed 200 mg 4 times / day every 6 hours. The duration of the prophylactic course of therapy is determined by the duration of the period when there is a risk of exacerbation.
Preventive treatment for organ transplants is carried out for 6 weeks.
For the treatment of primary genital herpes infections, 200 mg is prescribed 5 times a day for 5-10 days, with relapse 200 mg 5 times a day for 5 days. For prophylaxis, 200 mg 4 times a day or 400 mg 2 times a day for 6-12 months; against the background of pronounced immunodeficiency - 400 mg 4 times a day (treatment is continued for as long as the state of risk lasts).
For children under the age of 2, the dose is half the adult dose. At the age of 2 years, the drug is prescribed in the same dose as an adult.
For the treatment of varicella and shingles prescribed inside 800 mg 5 times a day every 4 hours, except during the night's sleep for 7 days.In patients with reduced immunity, it is advisable to / in the introduction. Children over 6 years old - 800 mg 4 times a day; 2-6 years - 400 mg 4 times a day; under 2 years old - 200 mg 4 times a day. More precisely, the dose can be determined at the rate of 20 mg / kg, but not more than 800 mg 4 times / day. The course of treatment is 5 days.
In / in drip adults and children over 12 years old (patients with infections caused by the herpes simplex virus) are prescribed 5 mg / kg 3 times a day (every 8 hours); patients with reduced immunity, herpetic encephalitis, chicken pox or shingles - 10 mg / kg every 8 hours, 3 times a day. The calculated dose is administered for at least 1 hour. For children from 3 months to 12 years, the dose for intravenous administration is calculated based on body area: infections caused by the herpes simplex virus - 250 mg / m2 of body surface every 8 hours; reduced immunity, herpetic encephalitis, chicken pox, shingles - 500 mg / m2. Newborns in the treatment of disseminated herpes - 10 mg / kg.
In patients with impaired renal function, correction of the dosage regimen is necessary. When creatinine clearance is less than 10 ml / min, the daily dose of the drug should be reduced to 400 mg 2 times a day, at intervals of not less than 12 hours. With QC 10-25 ml / min - 800 mg 2 times a day. In / in drip, for patients with CK 25-50 ml / min - 5-10 mg / kg 2 times a day, with CK 10-25 ml / min - 5-10 mg / kg 1 time per day, with CK less than 10 ml / min - 2.5-5 mg / kg 1 time per day subject to hemodialysis.
Possible: allergic reactions in the form of a skin rash.
Rarely: nausea, vomiting, diarrhea, elevated plasma bilirubin, elevated liver enzymes, increased urea, hypercreatininemia, headache, dizziness, increased fatigue, decreased concentration, hallucinations, drowsiness or insomnia, slight worsening of hematological parameters (erythropenia, leukopenia), fever, alopecia.
With prolonged use of the ointment, it is possible to peel at the place of its application, rarely - local irritation of the mucous membrane, erythema, burning sensation, pain.
When the / in the introduction - phlebitis, crystalluria, confusion, lethargy, hallucinations, irritability, drowsiness, tremor, convulsions, psychosis, coma.
Hypersensitivity to the drug.
Pregnancy.Lactation period (breastfeeding).
Tubular secretion blockers (probenecid) slow down the excretion of acyclovir (an increase of T1 / 2 by 18%).
When mixing solutions, it is necessary to take into account the alkaline reaction of acyclovir for intravenous administration (pH 11).
The increased effect is noted with the simultaneous appointment of immunostimulants.
It is recommended to begin treatment at the first signs of the disease.
Applying the cream is recommended to wear rubber gloves to prevent infection of other skin areas.
If necessary, the appointment of the drug during lactation should decide on the termination of breastfeeding.
To prevent crystallization in the tubular apparatus, the intake of large amounts of fluid is recommended; Adequate hydration is also required for i / o administration. In cases of impaired renal excretory function and the elderly, the dose is reduced, taking into account Cl creatinine.
Caution should be exercised when on / in the introduction of patients with neuropsychiatric disorders, abnormal liver function, electrolyte disorders, severe hypoxia.
With care, acyclovir is prescribed to patients of advanced age.
Patients with impaired immunity in herpetic mucous membranes are given intravenously. With often recurrent genital herpes, oral administration is most effective. Patients with impaired immunity in the case of shingles are prescribed inside or in / in.