Zerit

Zerit is an antiviral drug with systemic use. Included in the category of nucleoside, as well as nucleotide inhibitors of revertase.

Indications Zerit

It is indicated for the treatment of people with the HIV virus.

Release form

Available in the form of capsules with a volume of 30 or 40 mg. In one blister - 14 capsules. One package contains 4 blister plates - only 56 capsules are obtained in the package.

Pharmacodynamics

Stavudine is an artificial analogue of thymidine (nucleoside), which has antiviral properties. It is in vitro active against HIV within human cells. The effect of cellular kinases promotes its phosphorylation and conversion into stavudine triphosphate. This element inhibits the activity of HIV revertase, because it competes with the natural substrate of TTF.

The drug inhibits the process of DNA synthesis of the virus - it induces the termination of DNA chains. This is explained by the lack of the 3'-hydroxyl category required for the DNA elongation process. In vitro, stavudine triphosphate depresses DNA polymerase cells, exerting an overwhelming effect on the mtDNA binding process. Active actions relative to cells of DNA polymerase "a", as well as "b" are one hundred times less than actions related to HIV revertase. The in vitro passivation process, and in addition to the examination of isolated patients after treatment, allowed the detection of HIV-1 strains, which have a reduced sensitivity to stavudine. But the information about the development of HIV resistance with respect to stavudine in vivo is rather limited, as well as relative to cross-resistance to other analogues of nucleoside substances.

Pharmacokinetics

In adults, the bioavailability is 86 ± 18%. When oral doses of 0.5-0.67 mg / kg are taken, the concentration peak of the substance will be 810 ± 175 ng / ml. When taking the capsule inside the medication, peak and AUC values increase according to the dosage in the range of 0.033-4.0 mg / kg.

The half-life is not associated with dosage and is equal to 1.3 ± 0.2 hours when a single dose is used, and also 1.4 ± 0.2 hours with multiple drug administration. The intracellular half-life of stavudine triphosphate in vitro lasts 3.5 hours within the lymphocytes of the CEM type, and in addition inside the PBMC. This allows you to use the medicine twice a day.

The total indicator of the stavudine cleansing factor is 600 ± 90 ml / minute, and the clearance in the kidneys is 240 ± 50 ml / minute. This is evidence of active tubular secretion, and in addition to glomerular filtration.

Excretion of the substance is carried out with urine in unchanged form (approximately 34 ± 5% for single use, or 40 ± 12% for multiple). The residue in the form of 60% of the drug may be excreted by means of endogenous pathways.

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Dosing and administration

To improve the absorption of drugs, it is desirable to take it at least 1 hour before eating, while washing down with water (minimum 100 ml of liquid). If this recommendation can not be observed, it is allowed to use the drug with a light meal. If there are problems with swallowing the capsules, it is allowed to transfer the patient to a soluble form of the drug, or gently open the capsule, and then mix its contents with food.

The daily dosage is selected, taking into account the weight of the patient and other individual indices.

For children from 12 years and adults:

• with a weight of less than 60 kg, the dosage is 30 mg twice a day after every 12 hours;
• with a weight of 60 kg - 40 mg twice a day after every 12 hours.

Children 6-12 years old:

• with a weight of less than 30 kg - the dosage is 1 mg / kg twice per day, every 12 hours;
• with a weight of 30-60 kg - 30 mg twice a day, every 12 hours.

For adults with renal pathologies, dosage should be reduced in proportion to the creatinine cleansing factor:

• with a clearance rate of less than 50 ml / minute - 30 mg every 12 hours (with a weight of less than 60 kg) and 40 mg in the same mode (with a weight of 60 kg);
• with a KK of 26-50 ml / minute - 15 mg every 12 hours (weight less than 60 kg) and 20 mg in the same regime (weight from 60 kg);
• at a QC value less than 25 ml / minute - 15 mg every 24 hours (weight less than 60 kg) and 20 mg every 24 hours (weight from 60 kg); Also, if hemodialysis is performed at this KK, it is recommended to take the prescribed dose immediately after its completion. In days when there is no dialysis, the reception is carried out in the above mode.

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Use Zerit during pregnancy

Before starting the use of medicines, the doctor is required to know about the possible pregnancy of the patient or planning, since this remedy is allowed to be prescribed only when the potential benefit to the woman is higher than the possible risk of the fetus having negative consequences.

If a woman nurses a baby or plans to do so, you should warn her that this will cause the baby to become infected with HIV. Doctors forbid women with HIV to perform breastfeeding. It is required to stop feeding before the beginning of the treatment course.

Contraindications

Use of drugs is contraindicated in people with intolerance to stavudine or other components that make up the drug. In addition, it can not be administered to children under 6 years of age (use of capsules as a drug at this age is not recommended).

Side effects Zerit

In the treatment of HIV, it is difficult to distinguish adverse reactions in patients due to Zerit's use, from negative effects due to other drugs that are used in combination with the drug, as well as manifestations that develop in humans because of the pathology itself.

Observations of the condition of patients during the period of drug use showed the development of such negative reactions:

• general: the appearance of chills, headaches, abdominal pain, malaise. In addition, there were flu-like allergic manifestations, various neoplasms, and asthenia developed;
• digestive organs: vomiting, diarrhea and nausea, dyspeptic manifestations and anorexia; occasionally - constipation;
• organs of the respiratory system: development of dyspnea; occasionally pneumonia;
• organs of the National Assembly: a state of depression, dizziness, a sense of anxiety, a sleep disorder;
• Skin: itching, redness, severe sweating; benign tumors appeared less often;
• bone structure and muscles: joint pain, muscle pain;
• organs of the cardiovascular system: the appearance of pain in the chest;
• lymphatic and hematopoietic system: development of lymphadenopathy.

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Overdose

A single random drug overdose should not have serious consequences (there is evidence that 12 times the required daily dosage was not observed symptoms of acute poisoning). In the case of a chronic overdose, it is possible to develop a peripheral form of nephropathy or a disorder in the functioning of the liver. This will require medical supervision, and may also require the implementation of nonspecific deintoxication procedures. Hemodialysis coefficient of cleansing stavudine is 120 ml / min, but there is no information on the effectiveness of this procedure in case of an overdose of this substance. There is no information about the effectiveness of peritoneal dialysis.

Interactions with other drugs

Since zidovudine is able to inhibit the process of phosphorylation of stavudine within cells, it is forbidden to combine it with Zerit.

Combined use with lamivudine, didanosine, as well as nelfinavir does not affect the properties of the drug.

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Storage conditions

The drug should be kept in a dark place inaccessible to small children, under temperature conditions no more than 30 ° C.

Shelf life

Zerit is allowed to use within 2 years from the date of release of the drug.