ABRYSVO

Indications

• Asthma
• Chronic obstructive pulmonary disease (COPD)
• Bronchitis
• Pulmonary fibrosis
• Cystic fibrosis
• Respiratory distress syndrome

Dosage

Children: Refer to BNF for Children for appropriate pediatric dosing.

Adults: Refer to specific product guidelines and BNF for appropriate dosing guidelines.

Mechanism of action

The mechanism of action varies among different respiratory medications. Bronchodilators, such as beta-2 agonists, work by stimulating beta-2 adrenergic receptors in the airways, leading to relaxation of bronchial smooth muscle and dilation of the air passages. Corticosteroids reduce inflammation by inhibiting the production of inflammatory mediators and suppressing immune responses. Anticholinergics block the action of acetylcholine at muscarinic receptors, leading to reduced bronchoconstriction. Mucolytics help in thinning and loosening mucus, making it easier to expel.

Pharmacodynamics

The pharmacodynamic effects of respiratory medications are primarily observed in their ability to improve airflow, reduce respiratory distress, and enhance gas exchange. Bronchodilators provide rapid relief from acute bronchospasm, while corticosteroids exert a longer-term effect by decreasing airway hyperresponsiveness and inflammation. The efficacy of these medications is often assessed through improvements in lung function tests, symptom relief, and reduction in exacerbation frequency.

Pharmacokinetics

Pharmacokinetics may differ significantly among respiratory drugs. Generally, bronchodilators are rapidly absorbed and can have onset of action within minutes, with varying half-lives depending on the specific agent. Corticosteroids can have delayed onset of action, with systemic absorption dependent on the formulation (inhaled vs systemic). The metabolism of these medications often involves hepatic pathways, and elimination is typically renal. The bioavailability of inhaled medications is also an important factor affecting their therapeutic effectiveness.

Pregnancy

The safety of respiratory medications during pregnancy depends on the specific drug. Some may be used, while others are contraindicated. Always consult a healthcare professional.

Breast-feeding

Many respiratory medications can be used during breastfeeding, but it is essential to check specific drug safety profiles.

Storage

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

Indications

• Prevention of respiratory syncytial virus (RSV) infection in high-risk infants
• Preterm infants with a history of premature birth
• Infants with chronic lung disease (CLD) of prematurity
• Infants with congenital heart disease

Dosage

Children: Refer to BNF for Children for specific dosing guidelines.

Mechanism of action

Palivizumab binds to the F protein of respiratory syncytial virus (RSV), inhibiting the virus's ability to enter host cells. This neutralization prevents RSV replication and dissemination, thereby reducing the incidence and severity of RSV infections in at-risk populations.

Pharmacodynamics

Palivizumab has a long half-life, allowing for extended protection against RSV. Its mechanism of action contributes to the reduction of RSV-related hospitalizations and severe respiratory illness in vulnerable populations. The drug exhibits a high affinity for the RSV F protein, leading to effective neutralization of diverse RSV strains.

Pharmacokinetics

Palivizumab is administered intramuscularly and achieves peak plasma concentrations within a few days. It has a half-life of approximately 18 to 20 days, allowing for monthly dosing during the RSV season. The drug is primarily eliminated through proteolytic catabolism and does not undergo significant hepatic or renal clearance.

Pregnancy

The safety of synctial during pregnancy has not been established. Use only if potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether synctial is excreted in human milk. Caution should be exercised when administering to nursing mothers.

Storage

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

Indications

• Influenza
• HIV/AIDS
• Hepatitis B and C
• Herpes simplex virus infections
• Cytomegalovirus infections
• COVID-19
• Respiratory syncytial virus infections

Dosage

Children: Refer to specific antiviral agents for dosing guidance.

Adults: Refer to specific antiviral agents for dosing guidance.

Mechanism of action

Viruses infect host cells by attaching to specific receptors on the cell surface. Once inside, they hijack the host cell's machinery to replicate their genetic material and produce viral proteins. New viral particles are assembled and released from the host cell, often destroying the cell in the process. The specific mechanism can vary depending on the virus type, including integration into the host genome in retroviruses or utilizing specific pathways for replication.

Pharmacodynamics

The pharmacodynamics of antiviral agents depend on the specific virus and the mechanism of action. Antiviral drugs may inhibit viral entry into host cells, block viral replication, or prevent the assembly of new virions. The effectiveness of antiviral therapy often relates to the stage of viral replication and the immune response of the host.

Pharmacokinetics

Pharmacokinetics of antiviral drugs varies widely based on the specific medication used. Generally, antiviral agents are absorbed through the gastrointestinal tract and distributed throughout the body. They may undergo hepatic metabolism and are often excreted through the kidneys. The half-life of these drugs can range from a few hours to several days, influencing dosing schedules.