ACYCLOVIR DENK 200 Tablet

To treat viral infections (antiviral agent).

Herpes simplex, especially herpes genitalis infections of the skin and mucous membranes (primary and frequently recurring herpes genitalis).

In adult patients, suffering from very severe forms of very frequently recurring genital herpes simplex infections, an attempt may be made to use Acyclovir Denk 200 as a preventive treatment.

Dosage

Use in adults

For herpes simplex infections:

One single dose of 200mg acyclovir 5 times throughout the day at intervals of 4 hours.

For prophylaxis against severe forms and very frequently recurring genital herpes simplex infections:

Immunologically healthy patients are given a single dose of 200mg acyclovir 4 times daily at intervals of 6 hours. In individual cases, effective prophylaxis can also be achieved with a dosage of 200mg acyclovir 3 times daily at intervals of 8 hours or twice daily 200mg acyclovir at intervals of 12 hours.

For prophylaxis, immunosuppressed patients are given a single dose of 200mg acyclovir 4 times daily at intervals of 6 hours.

Severely immunosuppressed patients, e.g. after organ transplants, can be administered a single dose of 200mg acyclovir 4 times daily at intervals of 6 hours.

Use in children

For the treatment of herpes simplex infections, the adult dose is given to children over 2 years and half the adult dose to children below 2 years.

See the package insert about the details below:

- For patients with renal insufficiency

Method of administration

The tablet should be swallowed whole with adequate liquid (one glass of water) after meals.

Especially in patients with impaired renal function, adequate fluid intake should be ensured during treatment.

Special note: Acyclovir Denk 200 should be administered as early as possible after the first symptoms of an infection occur. Particularly in case of recurring herpes simplex infections the medicine should be taken upon the first signs of a renewed infection (i.e. itching, tension, first blisters).

Duration of treatment

The treating doctor will decide on the duration of treatment.

For herpes simplex infections, the duration of treatment is 5 days. However, this can be extended depending on the patient’s clinical status.

For the prevention of herpes simplex infections in immunologically healthy patients, the duration of treatment is dependent on the severity of disease and frequency of recurrence. However, it should not exceed a period of 6-12 months.

For prophylaxis against herpes simplex infections in severely immunosuppressed patients, the duration of administration is determined by the severity of immunosuppression and should be determined by the physician.

If you are allergic (hypersensitive) to acyclovir, valaciclovir or any of the other ingredients of this medicine.

If any of the following symptoms of severe allergic reactions occur, you must stop taking this medicine and seek medical assistance immediately:

- sudden difficulties in breathing, speaking or swallowing, shortness of breath,

- weakness, drop in blood pressure,

- swelling of the lips, tongue, face or throat.

Severe allergic reactions (anaphylactic reactions, angioedema, dyspnoea) are rare.

If any of the following signs occur that affect the nervous system, you must stop taking this medicine and seek medical assistance immediately: general physical restlessness, states of confusion, trembling, movement and speech disorders, delusion, depersonalisation, seizures, pathological brain changes, insomnia and impaired consciousness, including loss of consciousness.

These side effects, which wore off when the medicine was discontinued, have usually occurred in patients with damaged kidney function or other diseases that promote the onset of these unwanted effects. These side effects are very rare.

Common:

- dizziness, headache

- nausea, vomiting, diarrhoea and abdominal pain

- itching, skin rash, increased sensitivity to sunlight

Uncommon:

- nettle rash

- tiredness, fever

- diffuse hair loss has been reported with the use of acyclovir, although the relationship is unclear

Rare:

- increase in certain blood test results (liver values, kidney values, bile pigment, urea)

Very rare:

- decrease in the number of red or white blood cells, decrease in the number of platelets

- acute kidney failure, kidney pain

- liver inflammation (hepatitis), jaundice

The effect of Acyclovir Denk 200 will be prolonged if you are also taking

- probenecide

- cimetidine

- mycophenolate mofetil

However, no dose adjustment is necessary.

If treatment is necessary during pregnancy, the benefits must be carefully weighed up against the possible risks by a physician. After administration, acyclovir has been found in the mothers’ milk. It should therefore not be administered to nursing mothers.

- If your kidney function is impaired, a dose adjustment is required. The kidney function of elderly patients is often impaired. For this reason, your doctor may regularly check your kidney function.

- If your kidney function is impaired or your urine production is severely reduced, Acyclovir Denk 200 should not be taken to prevent infections.

- If you are taking Acyclovir Denk 200 at high doses, you should unsure that you drink plenty of liquids.

- If you have a severe immune system disorder.

Pharmacotherapeutic group: guanosine analogue, antiviral, viral DNA polymerase inhibitor

Aciclovir is a pharmacologically inactive substance which does not become an antiviral agent until after penetration into a cell infected with herpes simplex viruses (HSV) or varicella zoster viruses (VZV). This activation of aciclovir is catalysed by HSV- or VZV thymidine kinase, an enzyme that viruses particularly need for their replication.

In simple terms, one can say that the virus synthesises its own antiviral agent.

In more detail the following steps occur:

a) Aciclovir preferentially penetrates herpes-infected cells.

b) The viral thymidine kinase present in these cells phosphorylates aciclovir to aciclovir monophosphate.

c) Cellular enzymes convert aciclovir monophosphate to aciclovir triphosphate, the actual antiviral agent.

d) Aciclovir triphosphate has a 10-40 times greater affinity to viral DNA polymerase than cellular DNA polymerase and hence selectively inhibits activity of the viral enzyme.

e) Furthermore, the viral DNA polymerase incorporates aciclovir into the viral DNA, resulting in a chain termination during DNA synthesis.

Overall, these individual steps lead to a highly effective reduction in viral production.