Acyclovir for flu and colds

, medical expert
Last reviewed: 16.04.2020

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With the onset of the cold and wet season, the number of visits to the doctor for respiratory infections, which affects both children and adults, increases. Statistics claim that most colds are viral in nature and do not require antibiotic therapy. Given the characteristics of the life of viruses, scientists have come to the conclusion that the body itself is able to cope with the infection, if you help it a little. Immunostimulants and antiviral drugs are just such effective helpers. So, using one of the most popular drugs of this group, “Acyclovir” for colds and flu, you can stop the spread of infection due to exposure to the virus itself and the host's immunity.

How relevant is the treatment with Acyclovir?

Antiviral drugs are a relatively young invention of pharmacological science. The first drug of this kind was made in the middle of the last century. The need for such drugs was dictated by the widespread occurrence of colds, the cause of which is a viral infection.

If there were no doubts about how to fight bacteria after the invention of antibiotics, antiviral therapy raised many questions. The fact is that bacteria are extracellular parasites, and the penetration of potent drugs into the blood and tissue fluid quickly decided the outcome of their continued existence inside the person or on his skin. Viruses are intracellular parasites, which means access to them is limited.

Fighting intracellular infection is not so easy. After all, it is necessary to minimize the activity of infection, without affecting the properties of the cell, its biochemical composition, without causing mutations. Ideally, I would like to get rid of the virus forever, but some types of viral infection are so stable that they can only reduce its activity by creating conditions that impede the reproduction of virions. Such an infection, for example, is the herpes virus.

The incidence of herpes is extremely high, but many people simply do not suspect the presence of the virus in their body. Strong immunity contributes to this. But once he is given slack, herpes crawls to the surface, forming on the skin and mucous membranes, itchy foci covered with a vesicle rash. When the vesicles are opened, a wound surface is formed, which is a breeding ground for a bacterial infection, and therefore attracts it. Given that bacteria are always present on our skin, the risk of complications is extremely high. And if a herpetic rash brings mainly discomfort, then a bacterial complication carries a much greater danger.

Yes, but what does herpes have to do with colds and flu, because completely different viruses usually become the causative agents of acute respiratory viral infections (respiratory viral infections). So, the cause of the onset of flu symptoms is considered to be the virus of the orthomyxovirus family, which has 3 varieties (2 of them A and B cause epidemics, C are only isolated cases of the disease).

Any serotype of the influenza virus is transmitted by airborne droplets. The response of the body is the production of antibodies corresponding to hemagglutinin of a given infection serotype. With the stable functioning of the immune system, the body copes with the infection on its own in a short time. If this does not happen, the virus enters the bloodstream and begins to have a toxic effect on the body, increases vascular permeability, provokes pinpoint hemorrhages, negatively affects the functioning of various body systems, including the immune system.

Further weakening of the body's defenses that inhibit the activity of herpes infection (and it is present in 90% of adults), leads to the appearance of external symptoms of herpes and the attachment of a bacterial infection. Quite often, a cold is called not the fact of the disease that arose under the influence of the cold (it is he who initially weakens the immune system), but its manifestations in the form of herpetic eruptions on the lips, in the corners of the nose, inside it.

Viruses that provoke the development of respiratory infections force the immune system to give up all efforts to fight them, it is clear that there is simply no energy left to contain a latent herpetic infection. It is not surprising that in the early days of the disease a person experiences severe weakness and loss of strength. It was also commonplace that during acute respiratory viral infections, herpetic eruptions appear on the skin and mucous membranes of the face, which they call a cold. Genital herpes also enhances its activity, but few associate it with respiratory infections.

"Acyclovir" is a specialized drug active against the herpes virus. Therefore, the question of whether Acyclovir can be used for colds can have only one answer - a positive one. Not only possible, but also necessary in order to prevent the virus from spreading to large areas of the body and attract a bacterial infection.

“Acyclovir” is an antiviral drug that can cause herpes virus dysfunction, so many people understand its purpose for colds, but it’s not clear why doctors prescribe medicine for the flu, because the disease causes a completely different family of viruses. After reading the instructions for the drug and not finding in the indications for use mention of such diagnoses as acute respiratory viral infections or influenza, many allow themselves to doubt the relevance of such an appointment.

Yes, there is a separate group of antiviral agents whose action is directed specifically at the influenza virus: interferons (analogues of proteins produced by the immune system to deactivate the virus) and drugs with antiviral and immunostimulating effects (inhibitors of enzymes involved in the process of copying viral DNA on the eve of cell division, as a result of which makes the reproduction process impossible). The second group of drugs includes: Amantadine, Remantadin, Arbidol, Amizon, Relentsa, Immustat, Tamiflu and others. And if interferons can begin to be taken at any stage of the disease, then the drugs of the second group are more suitable for preventing or stopping the disease at an early stage (ideally during the incubation period).

"Acyclovir" in its action is close to the drugs of the second group. But it has its own characteristics. As a prophylactic, it is able to stop the development of both the herpes virus and the influenza virus. And in the post-incubation period (if you start taking the drug when the first symptoms of malaise appear), due to the immunostimulating action, it will prevent the onset of symptoms of herpes and will help to quickly deal with the pathogen of respiratory infection.

If the symptoms of herpes have already appeared, Acyclovir will inhibit the reproduction of the infection, i.e. An increase in the number and size of foci of herpetic rash, and the existing foci will disappear due to the strengthening of immunity (the body deactivates the remaining active virions). [1]

Since the vast majority of adults and a decent percentage of children on the planet are already infected with the herpes virus, we can say that Acyclovir will be useful in most cases of acute respiratory viral infections.

Indications Acyclovir

The treatment of colds with “Acyclovir” raises many questions in patients, mainly due to confusion in concepts. After all, we call a cold both a viral respiratory infection and its complication in the form of activation of the herpes virus. But ARVI does not cause herpes infection. And even if we are talking about viral (herpetic) tonsillitis, in fact it is just the activation of herpes in the mucous pharynx and tonsils, provoked by a weakening of the immune system, most likely, under the influence of other viruses and cold. In this regard, the role of Acyclovir in the treatment of respiratory infections becomes incomprehensible.

In the instructions for the drug, we do not find mention of the usual respiratory infections, combined by the acronym ARVI. In the paragraph where the indications for the use of the drug are listed, you can find:

  • treatment of infections of the skin and mucous membranes provoked by the herpes virus, including genital herpes, chickenpox and shingles,
  • prevention of recurrence of herpetic diseases.

And again, weirdness. If the drug treats cold sores, then what does chickenpox have to do with it - a highly infectious disease transmitted by airborne droplets?

Most people suffer from chickenpox in childhood and do not know that the disease, like the rash on the lips or genitals, is caused by the herpes virus. Yes, this virus is quite diverse, having several varieties (types).

Herpes viruses of types 1 and 2 cause a disease called herpes simplex. Type 1 virus is transmitted orally, so its manifestations are most often visible in the lips, less often near the nose, on its mucous membrane or on the pharyngeal mucosa. The second type of virus has a sexual transmission, which is why genital herpes spreads.

Herpes type 3 virus (zoster) is just that type of virus that is transmitted by airborne droplets and provokes the development of the disease, which we know as chickenpox. Like any type of herpes infection, this type of virus is resistant. Symptoms of the disease go away, but the virus remains in the body.

For the time being, antibodies produced by the immune system keep the virus inactive, but age-related and hormonal changes, frequent infections, chronic diseases, stress, overwork, weather conditions, HIV infection weaken the immune system and the virus reminds itself again, but it’s already somewhat otherwise. A one-sided rash appears along the sensory nerves, where the virus has been hiding for so long. An older disease with such symptoms is called shingles, although in essence it is still the same chickenpox of herpetic etiology.

Herpes virus type 4 (one of the most common) is the culprit of infectious mononucleosis - a benign disease that occurs with damage to the lymph nodes, liver, spleen, as well as some oncological diseases, for example, Barckitt's lymphoma.

Type 5 virus (cytomegalovirus) is transmitted through various body excretions. Like the previous type, it promotes the development of infectious mononucleosis, but can also cause hepatitis (inflammation of the liver) and the development of liver failure.

Scientists believe that there are at least 3 types of virus, but they have not been sufficiently studied. But this is not so important, because if we talk about the drug “Acyclovir”, then its effect is most relevant for the first 3 types of the virus that cause cold sores on the lips, nose and throat, genital herpes, chicken pox and its varieties of shingles. That is, it has widespread use, although not equally effective in different types of virus. Severe pathologies of the herpetic nature caused by types 4 and 5 viruses cannot be treated with an antiviral drug alone, so it makes sense to use it as part of complex therapy to reduce the activity of infection.

It becomes clear that "Acyclovir" can be prescribed both for the treatment of genital herpes or chicken pox, and for colds on the lips, which was caused by flu or SARS. Herpes in this case serves as a kind of complication of the flu.

Often during colds, herpetic eruptions also appear in the nose. Many attribute them to irritation due to a runny nose. The salt in the nasal secretions and mechanical friction can, of course, irritate the skin, but the specificity of the rash with herpes indicates its viral nature. A specific rash inside the nose is sometimes called a cold in the nose, and Acyclovir often becomes the drug of choice when this symptom occurs.

When prescribing the antiviral drug Acyclovir for colds and flu, the doctor has two goals at the same time: to prevent the development of a viral infection that caused the underlying disease (in particular, the flu), and to prevent the development of complications in the form of activation of a dormant herpes infection.

The drug exhibits little activity against the influenza virus, so it is usually prescribed to those patients who have previously been diagnosed with a herpes rash (according to the history or words of the patient). But for people with reduced immunity, the drug for internal use can be prescribed for preventive purposes, because for such people with a reduced protective barrier, herpes "clings" in the first place

Release form

When the herpes virus is in an inactive state in the body, it does not pose any danger and in no way affects the well-being of a person. That is why we do not suspect such a neighborhood, and we only go to the doctor if the dormant virus suddenly wakes up and begins to multiply actively, destroying skin cells and mucous membranes. So we learn about the presence of the virus, and its localization.

Knowing the localization of the virus, local treatment can be prescribed using external agents that will stop the reproduction of the virus and support local immunity, which will facilitate the rapid regeneration of affected tissues. With influenza and acute respiratory viral infections, you never know where the focus of herpes infection can occur, which is so attractive for bacteria, therefore, in the absence of external manifestations of herpes, it is more logical to prescribe systemic drugs, i.e. Drugs for internal use.

Manufacturers of Acyclovir provided all these points, therefore, the drug has several topical release forms: tablets of various dosings (200, 400 and 800 mg), ointment (2.5 and 5%), powder for the preparation of a solution used for drip intravenous administration in case of severe patient condition. There are also drugs that include the active substance acyclovir. So, “Genferon” (a combination of acyclovir and interferon) is available in the form of suppositories and can be used to prevent and treat herpetic symptoms both vaginally and rectally.

Ointment "Acyclovir" is used for colds, which has external manifestations in the form of a bubble rash in the lips, nose, eyes, and mucous membranes of the genitals. 3% ointment (ophthalmic) is intended for the treatment of herpetic foci on the mucous membranes of the eyes. %% - ointment and cream are used on the skin and in the genital area. This is an effective local treatment for herpes, which can be used both for primary infection and for relapses of infection.

Acyclovir tablets for colds can be prescribed both for prophylactic purposes and for the treatment of herpetic complications in the presence of acute respiratory viral infections and influenza. Before the appearance of a herpes rash, pills are the only way to prevent it. After the onset of herpes symptoms, combination therapy is prescribed, i.e. Systemic treatment is combined with local exposure. Topical use of Acyclovir for colds and flu increases local immunity, i.e. Protective functions of the skin and its ability to recover, and systemic - stimulates general immunity, which increases the body's strength in the fight against any viral or bacterial infection that has entered the body.


Considering the effect of the drug on the human body in various diseases, pharmacists and doctors pay attention to 2 main points:

  • How the drug acts on the causative agents of the disease and its symptoms (pharmacodynamics). The effectiveness of the drug in the treatment of specific diseases depends on this.
  • How is the absorption, metabolism and excretion of active substances in the body (pharmacokinetics). This affects both the effectiveness of the drug and its safety.

The pharmacodynamics, or mechanism of action, of Acyclovir is based on genetic research, because the active substance must deactivate the virus without affecting the cells in which it can hide.

The active substance of the drug (acyclovir) is able to interact with the enzyme thymidine kinase produced by healthy cells and infected. But his action is selective. Normal cell thymidine kinase does not affect the metabolism of acyclovir, but the enzyme produced by herpes virions inside a human cell converts the active substance into acyclovir monophosphate, which is subsequently converted into di- and triphosphate by chemical enzymes of the cell.

For the virus, the most dangerous is acyclovir triphosphate, which can integrate into the virus genome (viral DNA, hereditary material). Interacting with polymerase (the enzyme responsible for the synthesis of polymers of nucleic acids that make up the RNA and DNA chain), the acyclovir derivative inhibits its activity. This leads to the impossibility of replication (doubling) of DNA necessary for the reproduction (division) of virions. After all, the daughter virion should receive a copy of the DNA of the parent cell, in which the properties of the virus are inherited.

Thus, we can conclude that getting into the human body, acyclovir finds infected cells, changes its shape and properties, is embedded in the DNA of the virus and prevents its reproduction.

As for the pharmacokinetics of the drug, without going into details that are interesting only to specialists, we can mention the following points that must be taken into account when prescribing "Acyclovir" for colds and flu:

  • the drug does not have a pronounced neuro- and ototoxic effect, does not affect the structure and properties of body cells,
  • as a result of metabolic processes in the liver, an insignificant amount of an active metabolite is formed that provides a specific effect,
  • when applied topically, it is not absorbed into the blood on intact skin,
  • the ointment is absorbed more slowly than the cream, so it is better to use it on the exposed parts of the body, the cream is absorbed quickly, leaving no residue, so it can be applied under clothes,
  • most of the drug (about 85%) is excreted by the kidneys unchanged,
  • in patients with severe renal pathologies, drug elimination is significantly slowed, which increases its toxic effect (this must be taken into account when calculating the effective and at the same time safe dose of the drug).

Use Acyclovir during pregnancy

The need and safety of antiviral drugs during pregnancy is challenged by many women. Firstly, during this period it is better to limit the intake of any drugs, especially those that penetrate the blood. Secondly, there is evidence of the high toxicity of certain antiviral agents and the multiple side effects of interferon-based drugs. [2]

"Acyclovir", prescribed for influenza and the common cold as a prevention of recurrence of herpes infection and increase the body's defenses, does not belong to the group of interferons and does not have an obvious toxic effect. However, this relatively safe drug is also in doubt in many mothers. Nevertheless, its effectiveness against the influenza virus, which is dangerous for both the expectant mother and her unborn baby, is extremely small, and the herpes virus is dangerous for the baby only in contact with the active focus, which is possible only during and after childbirth.

Despite the absence of toxic and teratogenic effects on the fetus, an experienced doctor is unlikely to prescribe Acyclovir for prophylactic purposes. But with the appearance of a herpetic rash, the purpose of the drug is fully justified, at least for external use, nevertheless, an infectious complication when bacteria enter the wound can have much more unpleasant consequences, for example, blood poisoning.

The oral form of the drug during pregnancy is prescribed by doctors only if there is a serious risk to the mother's life that exceeds that of the fetus. But sometimes, the purpose of the drug is justified by the fact that its use prevents the transition of the disease from mother to child. So, a relapse of herpes on the eve of childbirth is fraught with an increased risk of contracting the baby's virus during passage through the birth canal. In this case, “Acyclovir” is the most optimal way out of the situation, because for a newborn any viral infection is a certain danger.

When breastfeeding, you need to remember that acyclovir passes into breast milk. True, its concentration in milk is much lower than in blood, and it is unlikely to harm a child, especially given that the drug does not act on healthy cells. However, do not exceed the dosage prescribed by your doctor. And if possible it is better to temporarily switch to artificial feeding. [3]


The drug "Acyclovir" is often prescribed for colds and flu, not only because of its effectiveness against the herpes virus, which is activated against a background of decreased immunity. The second reason for the popularity of the drug is the minimum of contraindications to its use.

So, the forms of the drug for external use are allowed to be used to treat children from birth, and the medicine in tablets (previously crushed and mixed with water or juice) is given even to one-year-old babies, choosing the optimal dosage. The drug is not prohibited during pregnancy or lactation.

“Acyclovir” treat both children and the elderly. Dose adjustment of the drug is required only for severe kidney damage, as a result of which the drug lingers in the body longer. Taking standard doses in this situation can lead to an overdose.

The only serious contraindication to the use of "Acyclovir" in any form of release is the individual intolerance to any of the components of the drug. Caution should be exercised in relation to patients with neurological disorders (given that the herpes virus, especially 3 types, is hidden in the nerve cells) and the dehydration of the body. Reception of "Acyclovir" implies a sufficient intake of water into the body, along with which the kidneys will also remove the spent drug. This is especially important if treatment is with high doses of acyclovir.

The tablets of some manufacturers contain lactose. This should be considered in patients with metabolic disorders of this component, i.e. With hereditary galactose intolerance, deficiency of lactase (an enzyme that breaks down lactose), as well as with glucose-galactose malabsorption syndrome.

Side effects Acyclovir

Regardless of the reason for prescribing the drug "Acyclovir", its tolerance is good by most patients. Complaints about the deterioration of well-being are extremely rare and are not always associated with taking the drug.

What can be the negative symptoms of an antiviral agent? Typically, these are gastrointestinal disorders characteristic of the peroral forms of Acyclovir. Abdominal pain, nausea, less often vomiting, and upset stools may appear. Similar symptoms most often appear in people with serious diseases of the digestive system.

In some cases, there is hyperactivity of the liver, as indicated by an increase in the blood of its enzymes. Other changes in the composition of blood are less common: an increase in the level of urea, creatinine, bilirubin, as well as a decrease in the concentration of leukocytes and red blood cells (leukemia and erythrocytopenia).

The central nervous system reaction to the drug may be as follows: the appearance of headaches, weakness, dizziness, drowsiness. Such symptoms occur infrequently. Even less often, patients complain of hallucinations, convulsions, impaired innervation of the vocal apparatus (dysarthria), tremors, discoordination of movements (ataxia), shortness of breath not associated with cardiovascular disease.

Pain in the kidney can occur in patients with diseases of this organ (renal failure, kidney stones, etc.).

Skin reactions often occur during the use of ointments and creams, but with increased sensitivity to the components of any form of release, itching, a small allergic rash (hives) may occur, and skin sensitivity to sunlight may increase. Allergic reactions usually occur in mild form, but with intolerance to the drug, anaphylactic reactions are also possible, for example, Quincke's edema.

Once again, we recall that such symptoms occur in rare cases. In addition, if Acyclovir is prescribed for colds and flu, it is sometimes difficult to distinguish the symptoms of the disease from the side effects of the medicine. The same can be said about the malaise of patients with multiple diseases and disorders in the body.

Dosing and administration

The instructions for the antiviral drug Acyclovir indicate recommended dosages for herpetic lesions, but there is no information on how to use the immunostimulant for colds and flu. The doctor, given the course of the disease (period of going to the hospital, symptoms, possible complications), can adhere to the manufacturer's recommendations or prescribe a different treatment regimen. In this case, it is better to trust a specialist who, thanks to his knowledge, will be able to determine the need for the drug for each specific patient, taking into account the individual and age-related characteristics of his body.

It is worth noting immediately that the drug in the form of a powder, used for intravenous infusions, is practically not prescribed for influenza, not to mention a mild cold. Usually, prescriptions are about tablets (used both for prophylaxis and for medicinal purposes) and their combined use together with external agents (ointment or cream). If there are no flu symptoms, and only a herpetic rash is present, only local treatment is possible, although its effectiveness is lower compared to the combined one.

According to the instructions Acyclovir tablets must be taken in dosages corresponding to the real cause of the disease. For the treatment of infections provoked by the herpes virus type 1 or 2, and for the prevention of relapse of the disease, the same single dose is used - 200 mg. But in the case of primary infection, this dose should be taken at intervals of 4 hours (about 5 times a day). If we are talking about secondary manifestations of infection (relapse), provoked, for example, by a flu virus or other pathology that weakened the immune system, the frequency of administration is reduced to 4 times a day (the interval between doses of the tablets is about 6 hours).

In patients with significantly reduced immunity (immunodeficiency due to HIV, bone marrow transplantation, etc.), a single dose can be increased to 400 mg without changing the frequency of taking the medicine. BUT if there are severe kidney diseases that reduce the excretion of the drug from the body, we can’t talk about increasing the dose. The treatment is individualized.

The course of prophylactic treatment with Acyclovir for colds and flu rarely exceeds 5 days.

Chicken pox caused by herpes simplex virus type 3 requires higher dosages of the drug. The effective single dose is 800 mg, and the frequency of administration remains the same as for the prevention of herpes type 1 and 2, i.e. 5 times a day at regular intervals.

The course of chickenpox in adults is usually severe, so a weekly course of treatment is required. For the same duration of the course, they also count on the treatment of shingles.

For colds and flu, the doctor may prescribe Acyclovir in tablets in slightly different dosages. If symptoms of herpes have appeared or the doctor is aware of a previous infection with herpes, the drug can be prescribed according to the following schemes:

  • 4-5 times a day, 200 mg,
  • 400 mg twice daily
  • 200 mg three times a day.

If the drug is prescribed for preventive purposes, i.e. There are no symptoms of herpes and there is no information about its presence in the body, doctors are often limited to low dosages: 2 or 3 times a day, 200 mg each.

The drug in the form of ointment or cream is applied to the foci of the herpetic rash 5 times a day, trying to adhere to the four-hour interval, for 5 (sometimes more) days. It is prescribed only with the appearance of external signs of the herpes virus. For prevention, these funds are not used.

"Acyclovir" for children with colds and flu

"Acyclovir" in tablets is intended for the treatment of patients older than 2 years, while a child of this age with colds is offered the dose recommended by adults, i.e. 200 mg 4-5 times a day (unless the doctor has prescribed another regimen). For children 1-2 years old, the medicine can be given in a dosage half that recommended (100 mg 4-5 times a day), but if there are no symptoms of herpes, it can be even less.

But is it necessary to give a small child a drug for the prevention of herpes, if he does not have such symptoms? You need to understand that the immune system in babies is formed at least 3 years old. During this period, the body's defenses cannot yet resist the pressure of the infection, so any contact with it can become decisive in the development of herpetic disease.

And if, in addition, the body is further weakened by the influenza virus, then what can prevent the herpes virus from entering it and starting active activity? The drug "Acyclovir" is an antiherpetic agent and an immunostimulant in one person. It is hardly possible to come up with prevention better than such a complex action, especially since the drug does not affect healthy cells and does not have a noticeable toxic effect.

If we are talking about the treatment of chickenpox, requiring high dosages, the appointment of the drug should be approached based on the age of the patient. Babies older than 2, but younger than 6 years of age, are prescribed the drug in a halved dosage. A single dose of 400 mg is offered 4 times a day.

For children over 6 years of age, a dosage of 800 mg is considered safe, which should also be given 4 times a day.

Since the course of chickenpox in children is easier than in adults, a 5-day treatment course is enough.

Doctors suggest treating local manifestations of herpes with colds and flu in children using external agents: ointments or creams. The dosage for children under 12 years of age is calculated based on the fact that for every square centimeter of the baby's body, no more than 10 mg of the drug can be used. For older children, the dosage can be increased fivefold, i.e. No more than 50 mg per 1 sq.cm.

Apply ointment or cream to the foci of the rash 4-5 times a day with an interval of 4 hours, if the kidney function in the child is not impaired. Otherwise, the dosage and treatment regimen is set individually. Usually, 5 days of local treatment are sufficient to obtain the desired effect, but if necessary, the course duration is increased.


In most drugs with a low probability of side effects, the patient's well-being is associated with exceeding the recommended doses or prolonged treatment with high doses of the drug. An overdose leads to inattention of patients.

Antiviral drugs similar to “Acyclovir” can be easily purchased at a pharmacy without a prescription or doctor’s prescription. The instructions for the drug indicate safe doses for all categories of patients. Particular attention is paid to children, the elderly and patients with kidney diseases, especially in cases where this organ is actively involved in removing the components of the drug from the body. If a patient with renal failure and urinary disorders begins to take standard doses of the drug, the medicine will accumulate in the body. Having reached a critical dose, it will affect the patient’s well-being,

As for Acyclovir, its critical dose is quite high. Even a random intake of 20 g of the drug per day did not lead to a noticeable disturbance in well-being (it is not worth checking!). But the fact that high doses of the drug did not have a toxic effect for the first time does not mean that in the future everything will be just as smooth. Repeated episodes of overdose provoked gastrointestinal upset, which lasted for several days.

Violations of the kidneys in healthy people and neurological disorders usually occur with an overdose of a solution of the drug "Acyclovir" for intravenous administration, which is usually not used for colds and flu.

If symptoms of an overdose appear, you need to rinse the stomach (if the drug was taken orally) and seek help from doctors. The procedures for hydration of the body (drinking regimen, droppers), symptomatic treatment are shown. To purify the blood from the active substance, hemodialysis is performed, which in this case is highly effective.

Interactions with other drugs

When making prescriptions, doctors are often interested in what drugs the patient is taking. This interest is not accidental, because the specialist is interested not only in the drugs that the patient takes in connection with the diagnosis that caused the request for medical help, but also drugs prescribed or taken without prescription to correct other disorders.

The fact is that many drugs tend to interact with other drugs and ethanol (alcohol), and the result of such a chemical reaction does not always give a positive effect. If the interaction can worsen the patient’s condition or minimizes the therapeutic effect, this must be mentioned in the instructions for the drugs.

The antiviral agent "Acyclovir", prescribed for colds and flu, as well as in the case of the appearance of a herpetic rash of a different etiology, did not have clinically significant interactions. This suggests that it fits perfectly into various schemes of complex treatment. Taking "Acyclovir" does not need to refuse to accept other previously used drugs.

Nevertheless, some points are worth considering. The antiviral drug Acyclovir is excreted by the kidneys by glomerular filtration. While taking other drugs with the same mechanism of removal from the body, it is important to understand that this increases the load on the organ, as a result of which the concentration of acyclovir in blood plasma may be slightly higher and the half-life is longer.

For example, probenecid and cimetidine can significantly increase the half-life of acyclovir, which means that it is worth reducing the frequency of taking the drug. Although, during normal kidney function, taking into account the low toxicity of acyclovir, dose adjustment in adults may not be necessary.

The same applies to interactions with immunosuppressants (inhibit natural immunity). On the one hand, the effect of drugs seems to be antagonistic, but against the backdrop of depression of immunity, help in the fight against viruses is simply necessary. The immunostimulating effect of antiviral agents is small, so the immunosuppressive effect remains quite sufficient. An increase in the concentration of acyclovir to the blood due to an increase in the half-life does not play a decisive role.

Storage conditions

Almost all medicines sold in pharmacies have a certain shelf life. Manufacturers usually mark two dates on the package with the drug: the date of manufacture and the final shelf life of the drug. The last date is considered mandatory, because after the expiration date many drugs not only lose their effectiveness, but also become dangerous to humans, because may cause severe intoxication.

The instructions for the drugs indicate the total shelf life of the drug, regardless of the date of release. Much depends on the composition of a particular form of the drug, so different excipients can be used by different manufacturers (only the content of the active or active substance should be constant). This explains the difference in shelf life of the same medicine.

"Acyclovir", as an effective therapeutic and prophylactic agent for colds and flu, has a decent history. Different pharmaceutical companies have been tackling the release of this popular antiviral drug for decades, but the technologies and components used (with the exception of the current one, i.e. Acyclovir itself) may be different, which is reflected in the composition and shelf life. So, “Acyclovir” in tablets of one manufacturer may have a shelf life of 2 years, other pharmaceutical companies guarantee the safety of the properties of the drug of their own production for 3 years. Store tablets at room temperature.

It is recommended to store the ointment for 2-3 years (see the instructions of a particular manufacturer), while the storage temperature should be below 15 degrees. True, freezing ointment or cream is also not worth it.

Reviews about the drug

Reading reviews of the drug "Acyclovir" once again make sure that how many people, so many opinions. Moreover, among those who purposefully use the drug against herpes infection and its relapses, there are those who smear warts, papillomas, and moles with ointment. Surprisingly, the drug “helps very well” for many (fight against human papillomavirus infection, remove moles?).

The benefit of such experimenters is not very much. Well, at least the drug is not toxic and can not cause harm. Most people use Acyclovir as intended, i.e. For the fight and prevention of herpes. True, not always as prescribed by a doctor.

For colds and flu, “Acyclovir” is prescribed less frequently, especially if there are no visible symptoms or reasons to expect their onset. Most often, an ointment is prescribed for a cold on the lips or near the nose, which occurs as a result of a decrease in immunity in viral respiratory infections. In this case, a cold is understood as the appearance of a vesicle rash characteristic of herpes. Bubbles tend to spontaneously open with the formation of a wet surface, and then a brown crust. The foci of infection are gradually increasing in size and may be infected with a bacterial infection.

But experience shows that prolonged use of the ointment is not always advisable. Apparently, over time, the virus develops resistance to the active substance, and the effect of the drug is gradually weakening. In this case, it is worth finding another antiviral agent. But it is important to pay attention to the active substance, which should be different. For example, it makes no sense to change "Acyclovir" to "Herpevir" or "Zovirax" - drugs with the same active substance.

In some cases, the action of the ointment is not enough to restrain the infection. By removing its foci in one place, one cannot count on the fact that they will not appear in another. A stronger and more stable effect can be achieved by taking pills and lubricating the foci of infection with ointment. Local treatment is unlikely to help those whose infection takes a strong position and reminds themselves with the slightest decrease in immunity. With frequent relapses without oral administration of “Acyclovir” one cannot count on a good effect.

The antiviral drug Acyclovir, according to its annotation, actively affects 5 types of herpes virus. But for some patients who are diagnosed with one of five types, the medicine does not help. This is explained by virus mutations, as a result of which strains resistant to long-used drugs appear. The same type of infection can include both sensitive and resistant strains. Thus, the virus tries to survive.

If the medicine does not help, do not experiment with doses and torture yourself. It is more logical to replace the drug with a medicine with another active substance, after consulting with your doctor first. The same should be done if an allergic reaction to Acyclovir occurs.

There are no references to side effects and toxicity of the drug. But a lot of experiences and doubts in future mothers. Many doubt even if the doctor prescribed the medicine.

I must say that the experiences of pregnant women are mostly groundless. According to many studies (although they are not enough to declare the medicine completely safe), the drug cannot harm not the expectant mother, nor her unborn child. An indication that Acyclovir should be used, given the risk ratio for the mother and the fetus, is a simple reinsurance, which, by the way, helps reduce the number of episodes of unauthorized use of drugs. Such notes can be found in annotations for many drugs.

If Acyclovir is prescribed by a doctor for colds or flu for a pregnant woman or nursing mother, one must rely on his professionalism. Moreover, the mechanism of action of the drug does not imply cellular changes that can affect the course of pregnancy or the development of the fetus. Viruses received from the mother, including those transmitted during childbirth or in contact with the skin of the baby in the postnatal period, have a much greater negative effect on the baby.


To simplify the perception of information, this instruction for use of the drug "Acyclovir for flu and colds" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.

Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.

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