Zanamivir (Dosing, Interaction, Side Effect, Administration, Etc..)

DEFINITION:

Zanamivir

is a medication

used

to treat and prevent influenza caused by influenza A and B viruses. It is a neuraminidase inhibitor and was developed by the Australian biotech firm Biota Holdings.

DRUG CLASS:
Antiviral
Neuraminidase Inhibitor, Influenza A&B Virus

DOSING:

Adult Dose

:
Influenza, Viruses Types A and B; Prophylaxis:
Household setting:
10 mg (two 5 mg inhalations) orally once daily (at approximately the same time each day) for 10 days (FDA

dosage

)

Community setting:
10 mg (two 5 mg inhalations) orally once daily (at approximately the same time each day) for 28 days (FDA

dosage

)
10 mg (two 5 mg inhalations) orally once daily for 7 days following exposure (guideline

dosage

)

Long-term care facilities and hospitals:
10 mg (two 5 mg inhalations) orally once daily for a minimum of 2 weeks: continuing up to 1 week after the last known case (guideline

dosage

)

Influenza, Virus types A and B:
10 mg (two 5 mg inhalations) orally twice daily (approximately 12 hours apart at about the same time each day) for 5 days
When possible, administer 2

doses

on day 1, at least 2 hours apart

Pediatric Dose:

Influenza, Viruses Types A and B; Prophylaxis:
Household setting, 5 years or older:
10 mg (two 5 mg inhalations) orally once daily (at approximately the same time each day) for 10 days (FDA

dosage

)

Community setting, adolescents:
10 mg (two 5 mg inhalations) orally once daily (at approximately the same time each day) for 28 days (FDA

dosage

)

5 years or older:
10 mg (two 5 mg inhalations) orally once daily for 7 days following exposure (guideline

dosage

)

Long-term care facilities and hospitals:
10 mg (two 5 mg inhalations) orally once daily for a minimum of 2 weeks: continuing up to 1 week after the last known case (guideline

dosage

)

Influenza, Virus types A and B:
7 years or older:
10 mg (two 5 mg inhalations) orally twice daily (approximately 12 hours apart at about the same time each day) for 5 days
When possible, administer 2

doses

on day 1, at least 2 hours apart

INDICATIONS:
FDA-Labeled Indications:
Influenza, Viruses Types A and B; Prophylaxis
Influenza, Virus types A and B

MECHANISM OF ACTION

:

Zanamivir

is an inhibitor of influenza virus neuraminidase affecting release of viral particles

ADVERSE EFFECT:
Common:
Respiratory:
Cough (influenza prophylaxis in pediatric patients: 16%)
Nasal symptom (influenza prophylaxis in pediatric patients: 20%)
Pain in throat (influenza prophylaxis in pediatric patients: 11%)
Respiratory depression

Other:
Fever with chills (influenza prophylaxis: 5%)

Serious
Cardiovascular:
Cardiac dysrhythmia

Dermatologic:
Rash

Immunologic:
Anaphylaxis
Hypersensitivity reaction

Neurologic:
Seizure

Psychiatric:
Abnormal behavior
Delirium

Respiratory:
Bronchospasm
Edema of pharynx

CONTRAINDICATION:
Hypersensitivity to

zanamivir

or any component of the product, including milk proteins

INTERACTION:

Zanamivir

is not a substrate nor does it affect cytochrome P450 (CYP) isoenzymes (CYP1A1/2, 2A6, 2C9, 2C18, 2D6, 2E1, and 3A4) in human liver microsomes. No clinically significant pharmacokinetic drug interactions are predicted based on data from in vitro studies. The concurrent

use

of

Zanamivir

with live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of potential interference between these products: LAIV should not be administered within 2 weeks before or 48 hours after administration of

Zanamivir

, unless medically indicated. The concern about possible interference arises from the potential for antiviral drugs to inhibit replication of live vaccine virus.

PHARMACOKINETICS:
Absorption:
Inhalation-Systemic: Bioavailability: 4% to 17%

Distribution:
NA

Metabolism:
NA

Excretion:
Inhalation-Systemic: Renal: unchanged; Fecal: Unabsorbed drug

Elimination:
Inhalation-Systemic: 2.5 to 5.1 h

PRECAUTION:
Administration:
Administration by mechanical ventilator or reconstitution in any liquid for nebulization is not recommended;

use

only with the provided Diskhaler; death due to ventilator obstruction has been reported

Concomitant Use:
Avoid

use

of intranasal live attenuated influenza vaccine (LAIV) within 2 weeks before, or 48 hours after,

zanamivir

administration, unless medically necessary

Immunologic:
Allergic-like reactions: including oropharyngeal edema,
Serious skin rashes: and anaphylaxis have been reported; discontinue

use

if an allergic reaction occurs or is suspected

Psychiatric:
Abnormal behavior and delirium leading to injury, primarily in pediatric patients: have been reported; monitoring recommended

Respiratory:

Use

not recommended with underlying airway disease, such as asthma or COPD, due to serious cases of bronchospasm, some fatal; if required, monitoring recommended
Serious and sometimes fatal cases of bronchospasm have been reported in patients with or without history of airway disease; discontinuation recommended if bronchospasm or decline in respiratory function develops

PREGNANCY CATEGORY:
Fetal risk cannot be ruled out.

BREASTFEEDING:
Infant risk cannot be ruled out.

MONITORING:
Symptomatic improvement indicates efficacy in treatment of influenza infection
Respiratory function; in patients with underlying airway disease

HOW TO TAKE OR ADMINISTRATION:
Inhalation:
Administer only with disk haler device provided
Do not reconstitute inhalation powder in any liquid formulation
Do not administer by any nebulizer or mechanical ventilator
If administered concurrently,

use

inhaled bronchodilator first

DOSAGE FORM:
Inhalation Disk:
5 MG/1 Actuation

TREATMENTS:
Management of Mild to Moderate Toxicity:
Treatment is predominantly symptomatic and supportive care.

Management of Severe Toxicity:
Treatment is symptomatic and supportive. Treat agitation with benzodiazepines. Treat seizures with

IV

benzodiazepines; barbiturates or propofol may be needed if seizures persist or recur.

TOXICOLOGY:
In clinical trials: oseltamivir oral

doses

up to 1000 mg have resulted only in nausea and vomiting. Intravenous

doses

of

Zanamivir

up to 600 mg were well tolerated in healthy volunteers. Additionally, for

Zanamivir

, up to 1200 mg/day

IV

for 5 days have been given to volunteers with minimal effects.

Zanamivir

intranasal

doses

up to 96 mg/day were administered to volunteers with no or minimal adverse effects. Oseltamivir-associated neuropsychiatric symptoms have occurred with high-dose therapy at 150 mg/kg two times daily for 2 days in a patient with influenza.

PATIENT COUNSELING OR CLINICAL TEACHING:
Warn patient not to

use

this drug in a nebulizer. It should only be

used

with the
Diskhaler device provided with the drug product.
This drug may cause diarrhea, nausea, headache, cough, and nasal symptoms.
Advise patient to immediately report signs or symptoms of bronchospasm and respiratory depression.
Instruct patient on proper inhalation technique




Disclaimer:
For the Registered Medical Practitioner Only. We are not recommended for self medication. self medication is may harmful for health. We are only information about medicine.