INFLUVAC VACCINE

Dosage

Children: Refer to specific drug information for appropriate dosing.

Adults: Refer to specific drug information for appropriate dosing.

Indications

• Vaccination against influenza
• Research in virology and immunology

Dosage

Children: Refer to specific vaccine guidelines for paediatric dosing.

Adults: Refer to specific vaccine guidelines for adult dosing.

Mechanism of action

Haemagglutinin binds to sialic acid-containing receptors on the surface of host epithelial cells. This binding triggers receptor-mediated endocytosis, allowing the virus to enter the cell. Once inside, the acidic environment of the endosome causes a conformational change in haemagglutinin, facilitating the fusion of the viral and endosomal membranes, which releases the viral RNA into the host cell cytoplasm.

Pharmacodynamics

Haemagglutinin is essential for the infectivity of the influenza virus. It mediates the attachment of the virus to host cells and is involved in the fusion process necessary for viral entry. The effectiveness of haemagglutinin as a target for vaccines is based on its ability to elicit a strong immune response, generating neutralizing antibodies that can prevent infection.

Pharmacokinetics

As a viral protein, haemagglutinin does not undergo traditional pharmacokinetic processes like absorption, distribution, metabolism, and excretion. Its function is directly related to its interaction with host cells during the viral infection process. Vaccines containing haemagglutinin aim to elicit an immune response without the need for absorption and metabolism in the conventional sense.

Pregnancy

Safety during pregnancy has not been established. Use with caution and only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is unknown whether haemagglutinin is excreted in human milk. Caution should be exercised when administering to breastfeeding women.

Storage

Store in a cool, dry place, away from light. Consult specific product information for temperature requirements.

Indications

• Influenza virus infection
• Prophylaxis of influenza in high-risk individuals
• Treatment of uncomplicated influenza in adults and children

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations based on the neuraminidase inhibitor used.

Adults: Refer to the BNF for specific dosing recommendations based on the neuraminidase inhibitor used.

Mechanism of action

Neuraminidase inhibitors, such as oseltamivir and zanamivir, block the active site of the neuraminidase enzyme, preventing it from cleaving sialic acid residues. This action inhibits the release of viral particles from the host cell surface, thereby limiting the spread of the virus within the respiratory tract.

Pharmacodynamics

Neuraminidase inhibitors exhibit antiviral activity against influenza A and B viruses. They reduce the duration of influenza symptoms and the risk of complications in at-risk populations. The effect is dose-dependent, with higher doses generally correlating with improved efficacy in viral load reduction.

Pharmacokinetics

The pharmacokinetic profile varies among different neuraminidase inhibitors. For example, oseltamivir is rapidly absorbed from the gastrointestinal tract, converted to its active form (oseltamivir carboxylate) in the liver, and has a half-life of approximately 6-10 hours. Renal excretion plays a significant role in its elimination. Zanamivir is delivered via inhalation and has a limited systemic absorption, with most of the drug acting locally in the respiratory tract.

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Headache
• Fatigue
• Dizziness
• Cough
• Insomnia

Precautions

• Use with caution in patients with a history of respiratory disease
• Monitor for allergic reactions in patients with known sensitivities
• Consider renal function in dosing adjustments

Pregnancy

Limited data on the effects of neuraminidase inhibitors during pregnancy. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Not known whether neuraminidase inhibitors are excreted in human milk. Caution is advised when administering to nursing mothers.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Oseltamivir - oral capsule
• Oseltamivir - oral suspension
• Zanamivir - inhalation powder

Dosage

Children: Refer to specific medication guidelines as Phuket is not a recognized drug.

Adults: Refer to specific medication guidelines as Phuket is not a recognized drug.

Pregnancy

Data on the use of phuket during pregnancy is not well-established. It is advisable to consult a healthcare provider before use.

Breast-feeding

The effects of phuket during breastfeeding are not clearly documented. Caution is recommended, and consultation with a healthcare provider is advised.

Storage

Store at room temperature, away from moisture and direct light. Keep out of reach of children.

Indications

• Bacterial infections
• Viral infections
• Epidemiological studies
• Antibiotic resistance monitoring

Dosage

Children: Refer to specific antimicrobial treatment guidelines based on the strain identified and the infection site.

Adults: Refer to specific antimicrobial treatment guidelines based on the strain identified and the infection site.

Mechanism of action

The mechanism of action for a strain depends on the type of microorganism it represents. For pathogenic bacteria, the strain may produce toxins, evade the host's immune response, or possess resistance mechanisms that allow it to survive in the presence of antibiotics. For viruses, strains may exhibit mutations that alter their ability to infect host cells or evade antiviral therapies.

Pharmacodynamics

Pharmacodynamics in the context of strains involves the interaction between the strain and the host's immune system, as well as the effects of specific antimicrobial agents on the strain. These interactions can influence the efficacy of treatments and the development of resistance.

Pharmacokinetics

Pharmacokinetics is not directly applicable to strains themselves but rather to the drugs used to treat infections caused by specific strains. Factors such as absorption, distribution, metabolism, and excretion of antimicrobial agents can vary depending on the strain's characteristics and the site of infection.

Pregnancy

There is limited information on the safety of strain in pregnancy. It is advisable to consult healthcare professionals for guidance.

Breast-feeding

Safety during breastfeeding is not well established. It is recommended to seek medical advice before use.

Storage

Store in a cool, dry place, away from direct sunlight and moisture. Keep out of reach of children.

Dosage

Children: Refer to the specific drug's prescribing information for paediatric dosing.

Adults: Refer to the specific drug's prescribing information for adult dosing.

Mechanism of action

The mechanism of action for any specific drug categorized under 'used' would depend on the active ingredient. Generally, drugs may act through various pathways such as receptor binding, enzyme inhibition, or modulation of signaling pathways. Understanding the specific drug is essential to delineate its precise mechanism of action.

Pharmacodynamics

Pharmacodynamics refers to the effects of the drug on the body, including the relationship between drug concentration and effect. This could include therapeutic effects, side effects, and toxicity, which are influenced by factors such as receptor affinity, intrinsic activity, and the drug's pharmacological class. Again, specifics will depend on the particular drug in question.

Pharmacokinetics

Pharmacokinetics involves the absorption, distribution, metabolism, and excretion (ADME) of a drug. Key factors include bioavailability, volume of distribution, half-life, and clearance. Each drug's pharmacokinetic profile will determine its dosing regimen and duration of action, which is critical for achieving therapeutic effects while minimizing adverse reactions.

Adverse effects

• Nausea
• Vomiting
• Dizziness
• Headache
• Fatigue

Precautions

• Use with caution in patients with a history of gastrointestinal disorders
• Monitor for signs of allergic reactions
• Consider potential interactions with other medications

Pregnancy

Safety during pregnancy has not been established. Use only if clearly needed.

Breast-feeding

It is not known whether this drug is excreted in human milk. Use with caution.

Storage

Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.