Zanamivir
Zanamivir Uses, Dosage, Side Effects, Mechanism of Action, How Long Does it Take to Work? Zanamivir is a brand name. Its generic name is Zanamivir.
Zanamivir Introduction
Zanamivir is an antiviral medication used to treat and prevent influenza (flu) caused by influenza virus A and B. It is a neuraminidase (NA) inhibitor, derived from a compound found in the genetic material of a strain of bacteria isolated in the 1970s. It works by blocking the activity of the enzyme neuraminidase, preventing the virus from releasing new virus particles, thus stopping the spread of the virus.
Uses of Zanamivir
Zanamivir is used in adults and children 7 years and older to reduce the risk of influenza A and B. It is also used to treat uncomplicated influenza (flu). It is used as a preventative measure in adults and adolescents 15 years and older.
Mechanism of Action
Zanamivir works as an inhibitor of neuraminidase, an enzyme produced by the influenza virus. It works by binding to the active site of the viral neuraminidase, blocking the release of new virus particles from infected cells. This helps to stop the spread of the virus and reduce the severity of the illness.
How Long Does It Take to Work?
Zanamivir begins to work within 1 to 2 days after the start of treatment. The duration of response depends on the underlying severity of infection and the patient's response to the treatment.
Absorption
Zanamivir is absorbed poorly after oral administration. It is best absorbed when administered by inhalation. The systemic bioavailability of zanamivir after inhalation is estimated to be 1 to 2 percent.
Route of Elimination
Zanamivir is eliminated primarily by renal excretion. Approximately 10 percent is eliminated in feces.
Dosage
The usual dose for adults is two inhalations (5 milligrams per inhalation) taken twice daily (10 milligrams total twice daily). For children 7 years of age and older, the usual dose is two inhalations (5 milligrams per inhalation) taken once daily (10 milligrams total once daily). The inhaler should be used at least 15 minutes prior to exercise or activity to ensure maximum absorption of the drug.
Administration
Zanamivir should be inhaled using the Diskhaler inhaler device. The disk should be inserted into the device and the device should be primed for first use. After loading the disk, the patient should inhale the medication slowly and deeply, then exhale slowly. The patient should repeat the process for two inhalations twice a day. It is important to use a clean mouthpiece for each use.
Side Effects
Common side effects of zanamivir include bronchospasm, cough, and nasal/throat irritation. Other side effects include headache, dizziness, nausea, vomiting, and diarrhea.
Toxicity
Zanamivir is generally well tolerated. However, withdrawal of treatment due to intolerability of side effects has been reported in some studies.
Precautions
Patients should not use zanamivir if they are allergic to it or any of its ingredients. Additionally, zanamivir should not be used in patients with severe asthma as it may cause bronchospasm. Patients should talk to their doctor before using any other medications, including over-the-counter medicines, vitamins, or herbal supplements.
Interaction
No interactions between zanamivir and other drugs have been reported. However, concurrent use of zanamivir with certain medications may increase the risk of adverse events, such as bronchospasm.
Disease Interaction
Patients with certain diseases may be at increased risk when using zanamivir, including those with chronic lung or breathing problems, heart problems, high blood pressure, or kidney problems. Patients should talk to their healthcare provider before using zanamivir.
Drug Interaction
No drug interactions have been reported between zanamivir and other medications. However, concurrent use may increase the risk of adverse reactions, such as bronchospasm.
Food Interactions
No food interactions with zanamivir have been reported.
Pregnancy Use
Zanamivir is classified as pregnancy category C drug, which means that it may be harmful to a developing fetus. Therefore, it is important for pregnant women to talk to their doctor before using zanamivir.
Lactation Use
It is not known if zanamivir is excreted in human milk. Therefore, caution should be exercised when using zanamivir while breastfeeding.
Acute Overdose
No data are currently available on the acute toxicity of zanamivir. Treatment of acute overdose should be supportive and symptomatic.
Contraindication
Zanamivir is contraindicated in patients who are hypersensitive to any component of the drug such as eggs or chicken protein.
Use Direction
For the best results, zanamivir should be used as directed by a healthcare provider. Patients should use the inhaler correctly to ensure that the medication is absorbed adequately by the body. Patients should not use a spacer or mouthpiece unless directed by their provider. The inhaler should be cleaned and air-dried before each use.
Storage Condition
Zanamivir should be stored in a cool, dry place and away from light. The inhaler should be kept in its protective case when not in use.
Volume of Distribution
The volume of distribution of zanamivir after inhalation is approximately 2.5-3.7 L/kg.
Half Life
The elimination half-life of zanamivir after inhalation is approximately 1.9 hours.
Clearance
The clearance of zanamivir following inhalation is approximately 30 mL/min.
Here you find in details version of Zanamivir