Relenza

Relenza is an antiviral drug.

[1],

Indications Relenza

It is used to treat or prevent the development of infections, the activity of which is provoked by influenza viruses that have A or B type. The use of medication helps to reduce the symptoms of the disease and significantly reduce its duration.

[2], [3], [4]

Release form

The release of the substance is in the form of a metered-dose powder for inhalation. A blister pack (rotadisk) has 4 cells containing 5 mg of powder (zanamivir) and a special device through which the powder must be inhaled (dischaler). Inside the box contains 1 diskhaler and 5 rotadiskov.

[5], [6]

Pharmacodynamics

The drug is a neuraminidase inhibitor with high selectivity. Neuraminidase acts as a surface enzyme of the influenza virus; it has the ability to release cells and accelerate the movement of the virus through the mucosal barrier to the surface of epithelial cells, resulting in infection of other cells of the respiratory ducts.

The mucosa treated with zanamivir inside the respiratory tract retains the virus that falls on it, preventing it from penetrating into the epithelial cells. When processing already damaged cells of the respiratory ducts and nasopharynx, the spread of the virus inside the body stops. The medicine does not penetrate inside the cell space, exerting its influence in the extracellular region.

The drug is highly effective in preventing the development of influenza. In comparison with the placebo group, its effectiveness is within 67-79%, and in comparison with the active observation group - within 56-61%.

[7], [8]

Pharmacokinetics

With the introduction of the substance through inhalation, its bioavailability reaches only 2%. The level of systemic absorption is approximately 10–20%. At 1-fold use of 10 mg dosage, Cmax values are noted after 75 minutes and make up 97 ng / ml. Since the drug has a low absorption rate, its plasma values are also low.

The distribution of the active element after the procedure of inhalation occurs within the tissues of the respiratory system. Substance indicators after 12 and 24 hours from the moment of inhalation, on average, respectively, are 340 and 52 times higher than the average level of half-maximum retardation of the virus neuraminidase. A large amount of the drug component inside the respiratory tract provides a rapid slowdown in the activity of the neuraminidase virus.

The drug is cumulated inside the lung tissue (13.2%) and the tissues of the oropharynx (77.6%).

Excreted unchanged through the kidneys, without undergoing metabolic processes. The half-life of the substance after the inhalation procedure is 2.6-5 hours. The level of total clearance - in the range of 2.5-10.9 l / h.

[9], [10], [11], [12],

Dosing and administration

The medicine must be administered using a special inhaler, a diskhaler, which is contained in the package of the medicament along with the powder. For any age, a standard dose of 20 mg per day is used. In order for therapy to have the maximum effect, inhalation should begin immediately after the discovery of even mild manifestations of the disease.

It is necessary to inject the substance in 2 doses (each portion is 10 mg of zanamivir in the form of inhalation - 2 treatments of 5 mg). The duration of the drug is 5 days.

In order to prevent the drug can be used for ten days, two inhalations (10 milligrams of the active substance) once a day. If the risk of infection persists, prophylactic use can be extended to one month.

Use Relenza during pregnancy

You can not prescribe medication in the first trimester of pregnancy.

Contraindications

Main contraindications:

• history of allergy to zanamivir;
• breastfeeding period;
• increased sensitivity of the bronchi relative to inhalants;
• diseases that cause spasms of the bronchi;
• gastro-lactase.

[13], [14], [15], [16]

Side effects Relenza

The use of the drug may cause the occurrence of such adverse symptoms:

• epidermal reactions - urticaria, Stevens-Johnson syndrome, erythema multiforme, and PET;
• difficulty of the respiratory process;
• bronchospasm;
• manifestations of allergy - swelling of the larynx or face;
• social deviation;
• hallucinations, delirium or convulsions.

[17], [18],

Overdose

The probability of accidental intoxication Relenzey extremely low. In the case of an intentional increase in the portion to 64 mg per day, the development of negative symptoms was not observed.

In the case of parenteral administration of drugs in 1200 mg portions per day for 5 days, no negative signs were also recorded.

[19], [20]

Interactions with other drugs

It is forbidden to perform inhalation of this medication in combination with bronchodilators with a fast type of exposure. If there is a need to use them, these drugs are administered first, and then perform inhalation using zanamivir.

[21], [22]

Storage conditions

Relenza must be kept at temperatures not exceeding 30 ° C.

[23]

Shelf life

Relenza can be used within 5 years from the date of manufacture of the drug.

Application for children

Do not use for children under 5 years of age.

[24], [25], [26], [27]

Analogs

Analogues of the medicament are such drugs as Virolex, Virgan, Amizon, Valtrex and Virogel with Nucleavir and Rebetol, as well as Acyclovir.

[28], [29], [30], [31], [32]

Reviews

Relenza has a high therapeutic efficacy, significantly reducing the pathological symptoms after the first inhalation procedures. Also in the feedback indicates that the use of drugs rarely causes the appearance of side effects.