In the article, we will understand how Acyclovir helps.
It is an antiviral medication for oral use that is active against herpes simplex viruses, herpes zoster virus and genital herpes.
Composition and release forms
According to the instructions, "Acyclovir" is produced in several pharmacological forms:
- Cream for external use - available in aluminum tubes of 10 g, 5 g, 2 g.
- Ointment "Acyclovir" - in aluminum tubes of 10 g, 5 g, 3 g and 2 g, as well as in glass jars of 20 g, 10 g and 5 g.
- Eye ointment - in 5 g aluminum tubes
- Lyophilisate for the manufacture of solutions for infusion - is produced in 500 mg and 250 mg vials.
- Tablets - available in blisters of 10 pieces of 400 mg and 200 mg in one tablet.
The active element of this pharmacological agent is acyclovir. Reviews about the drug are abundant.
pharmachologic effect
"Acyclovir" is an antiviral medication for parenteral, oral, local and external use, a synthetic analogue of an acyclic purine nucleoside. The drug has high specificity for Herpes simplex viruses, including the first and second types, cytomegalovirus, Epstein-Barr virus and Varicella zoster. The manifestation of the highest activity of the active substance is observed to HSV-1 and to HSV-2, VZV, EBV and CMV (descending). The action of “Acyclovir” is due to the penetration of the drug into virus-infected cells that produce viral thymidine kinase, as a result of which the active element of the drug is phosphorylated to acyclovir monophosphate.
The activity of thymidine kinase to acyclovir is much higher than the effect of cell enzymes on it (the concentration of acyclovir monophosphate in cells affected by infection is 40-100 times higher). Subsequently, the formation of acyclovir triphosphate, which is a selective and highly active inhibitor of DNA polymerase. The mechanism of suppression of DNA synthesis by acyclovir triphosphate consists in the fact that it is a substrate for this enzyme, which allows the 3'– 5 'bond required to extend the DNA chain. In this case, an early break in the DNA chain occurs.
As indicated by the instructions for "Acyclovir", tablets of this medication after oral administration are partially absorbed in the intestinal lumen. After a five-day intake of 200 mg per day, the maximum concentration of the active substance in the blood is 0.3-0.8 μg / ml. The substance binds poorly to plasma proteins. It is excreted mainly through the urinary system. Renal clearance is significantly higher than creatinine, which indicates that the active element is excreted by tubular secretion. The only metabolite is 9-carboxymethoxymethylguanine.
Indications for appointment
According to the annotation for use, Acyclovir tablets are prescribed for the treatment of the following pathologies:
- recurrent and primary genital herpes, which occurs in severe form;
- primary and recurrent herpes simplex, characterized by damage to the mucous membranes and skin, provoked by Herpes simplex of both types, in patients with impaired immunity;
- herpes zoster, provoked by Varicella zoster;
- herpes zoster, which is accompanied by eye damage.
The oral administration of this medication is indicated for the prevention of recurrent cases of genital herpes, as well as herpes zoster and ordinary herpes caused by Varicella zoster in cases of immune defense.
Parenteral drug is prescribed for the treatment of encephalitis caused by both types of Herpes simplex, as well as generalized infections in newborns provoked by Herpes simplex.
During the treatment of chickenpox within 24 hours after the appearance of typical rashes of rash during normal functioning of the immune system, the medicine “Acyclovir” is taken orally inside, in case of impaired immunity - by the parenteral method.
Contraindications
The use of all pharmacological forms of the medicine "Acyclovir" is contraindicated in case of hypersensitivity to the components present in its composition.
Absolute contraindications for the tablet form of the medication are:
- lactase deficiency;
- galactose-glucose malabsorption;
- lactose intolerance;
- age up to 1 year;
- lactation.
Relative contraindications
Relative contraindications for Acyclovir tablets (use under medical supervision) include:
- neurological disorders resulting from the use of cytotoxic drugs (including, with a burdened history);
- impaired renal function;
- the use of high doses of the drug, especially with dehydration;
- pregnancy;
- elderly age.
Ointment is relatively contraindicated in:
- individual intolerance;
- the presence of purulent or ulcerative lesions on the skin;
- open wounds and bacterial infections of the skin;
- children under one year old;
- pregnancy and lactation.
An absolute contraindication for the use of Acyclovir ointment for the eyes is lactation. Under the supervision of a specialist, eye ointment is prescribed during pregnancy.
An absolute contraindication for the use of infusion solutions is breastfeeding, and the relative ones are dehydration, kidney failure, neurological and electrolyte disorders, severe forms of hypoxia, reactions to the use of cytotoxic drugs, concomitant therapy with drugs that impair the function of the kidneys (for example, cyclosporins), pregnancy .
Dosage regimen and methods of application
For patients with primary infections and recurrent Herpes simplex virus, mucous membranes and skin are prescribed 1 tablet 5 times a day. The duration of medication is 6 days. Longer treatment can be prescribed for severe forms of the disease. With a significant weakening of the immune system, it is possible to double the dosage or intravenous use of the drug.
To prevent the development of relapses with normal immunity, 1 tablet is usually prescribed 4 times a day. With reduced immunity, an increase in the dosage of "Acyclovir" is required.
With local therapy, a cream or ointment of this medicine is applied with a cotton swab to the affected areas and neighboring skin areas. Multiplicity of use - 5 times a day. Therapy is continued until the formation of crusts on the ulcers or until they are completely healed. The average duration of therapy is 10 days.
For example, how to treat a herpes infection around the mouth and under the nose? The ointment is applied to the affected areas three times a day, previously the skin should be cleaned of dust and cosmetics. The course of therapy should be at least five days.
Shingles in the complex therapy with ointment are treated for about seven days, and the drug is applied to the affected areas for another three days after the clinical symptoms of the disease disappear. This is done in order to prevent a relapse of the infection. The total duration of ointment therapy should be no more than 10 days. If there is no improvement during this time, then you need to re-visit the doctor, clarify the correct diagnosis and evaluate the adequacy of the treatment.
Intravenously after 12 years and adults are prescribed 5-10 mg / kg. For children from 1 year to 12 years, the dosage of Acyclovir is calculated based on the area of the skin.
Side effects
According to reviews, "Acyclovir" can cause the following negative reactions:
- allergic skin symptoms;
- anaphylactic reactions ;
- increased enzymatic activity of the liver;
- confusion of consciousness;
- fever;
- hallucinations;
- lymphadenopathy;
- cephalgia;
- leukopenia;
- vision change;
- peripheral edema.
With parenteral use of the drug may occur:
- inflammation at the injection site;
- phlebitis;
- renal failure;
- symptoms of encephalopathy;
- hematological changes;
- hematuria;
- hemolysis;
- lowering blood pressure;
- nervous disorders;
- psychosis;
- digestive tract dysfunction.
Taking pills can provoke:
- malaise;
- paresthesia;
- violation of the functions of the digestive tract;
- alopecia;
- agitation;
- myalgia;
- dizziness, drowsiness.
Overdose symptoms
The main symptoms of an overdose of the drug “Acyclovir” are agitation, coma, convulsions, lethargy. If the concentration of the main element exceeds the solubility in the tubules of the kidneys (2.5 mg / ml), its precipitation in them may be noted. Treatment for an overdose is symptomatic.
Effect on reaction rate
Infusion solutions are intended exclusively for use in a hospital environment, therefore, there is no data on the effect of treatment on the ability to drive vehicles.
Treatment with Acyclovir in any pharmacological form during pregnancy and breastfeeding can be carried out under the supervision of a doctor after assessing the expected benefits and possible risks.
Drug interaction
With the concomitant use of probenecid, the average half-life of the drug increases and the clearance of acyclovir decreases. Concomitant use with nephrotoxic drugs increases the likelihood of developing impaired renal function, with immunostimulants - increases the effectiveness of acyclovir.
Use of the drug for chickenpox
"Acyclovir" with chickenpox in children is often prescribed. This drug has an overwhelming effect on the vital activity of herpes viruses and those that cause chickenpox.
The drug is able to penetrate into pathogenic cells, taking the form of a nucleotide - a molecule necessary for building the DNA of the virus. Having come into contact with such a nucleotide, viruses die together with the infected cell, as a result of which the development of the disease ends. Drug substances have an effect only within the affected cells, without affecting healthy structures.
When using "Acyclovir" with chickenpox in children, the following effects are observed:
- reduction in the duration of febrile syndrome;
- reduction in the number of skin rashes.
The medication does not affect infectiousness and does not reduce the overall duration of the disease, but significantly alleviates its symptoms. For children, the drug is prescribed for immunodeficiency states that are caused by diseases such as HIV.
Analogs
Analogs of the medicine "Acyclovir" are:
- Herperx;
- Zovirax
- Vivorax;
- Medovir;
- "Acyclostad";
- "Provirsan";
- Virolex
- "Valcite";
- "Trivorin";
- Ribavirin
- Virazole;
- Arviron;
- Rebetol;
- Valtrex
- "Tsimeven";
- "Valacyclovir";
- "Vatsireks";
- Valvir
- "Valogard";
- Vairova;
- Ribavin;
- "Famvir";
- "Minaker."
Reviews about "Acyclovir"
Most reviews about this medicine are positive. It is considered effective, affordable and inexpensive. The speed with which the therapeutic effect of the cream for external use is achieved is evaluated differently. Some patients say that improvement occurs rather quickly, while others indicate that the disappearance of symptoms does not occur immediately and the use of the drug can provoke the development of various side effects.
In addition, there are negative reviews regarding the consistency and bitter taste of the drug. Tablets are used, as a rule, in cases where it was not possible to eliminate the manifestations of pathology with external medicines. Patients note that good results are achieved when using a medical product with the development of the first symptoms. As for the side effects from the use of all dosage forms of this medication, among them the most frequently observed symptoms in patients were nausea, dizziness, headaches, and digestive irritation. This is confirmed by reviews of Acyclovir.
The main advantages of the ointment for the eyes are its high efficiency, reasonable price and convenient packaging. The disadvantages include a small volume of the tube.
Reviews of experts suggest that this medication is one of the first that is prescribed for specific viral diseases. Doctors indicate that “Acyclovir” fights well with the infections indicated in the description of the drug, but it should not be prescribed on its own, but only by a specialist who will correctly select the dosage and form of the drug.
Patients who used this drug in the treatment of chickenpox were satisfied. It was noted that the healing of rashes occurs very quickly, and the pathological process itself proceeds in a milder form. Rashes quickly crusted, healed and did not leave scars and scars.
We examined how Acyclovir helps.