DOLIO SABIN ONE AND THREE (ORAL)

Indications

• Prevention of poliomyelitis infection
• Vaccination in children and high-risk populations

Dosage

Children: Refer to the BNF for Children for specific dosages and recommendations for vaccination schedules.

Adults: Refer to specific vaccination guidelines for adults, as dosages may vary based on risk factors and prior vaccination history.

Mechanism of action

Poliovirus enters the body through the oral route, replicating in the oropharynx and gastrointestinal tract before spreading to the central nervous system via the bloodstream. Once inside the CNS, the virus selectively infects motor neurons in the anterior horn of the spinal cord, leading to cell lysis and resulting in muscle weakness or paralysis. The immune response to the virus contributes to inflammation and further neuronal damage.

Pharmacodynamics

The poliovirus's pathogenicity is primarily due to its ability to evade the host's immune response and its selective neurotropism. The destruction of motor neurons leads to flaccid paralysis, with recovery possible in some cases as the motor neurons may regenerate. The severity of the disease correlates with the extent of neuronal involvement, which can vary widely among individuals.

Pharmacokinetics

Poliovirus is an RNA virus that does not undergo traditional pharmacokinetic processes as it is not treated with drugs. Instead, the prevention of polio relies on vaccination strategies. The inactivated poliovirus vaccine (IPV) and the oral poliovirus vaccine (OPV) are used to induce immunity. After administration, the vaccines promote the development of antibodies against the virus without causing disease.

Contra-indications

• Hypersensitivity to the vaccine component
• Severe immunodeficiency
• Acute febrile illness

Adverse effects

• Pain at injection site
• Fever
• Fatigue
• Headache
• Nausea
• Allergic reactions

Interactions

• Immunosuppressive therapies may reduce vaccine efficacy
• Concomitant administration with other vaccines may affect immune response

Precautions

• Use with caution in individuals with moderate to severe acute illness
• Consider history of allergic reactions
• Monitor for signs of anaphylaxis after administration

Pregnancy

Poliomyelitis vaccination is generally considered safe during pregnancy, but consult a healthcare professional.

Breast-feeding

The vaccine is considered safe for breastfeeding mothers.

Storage

Store at 2 to 8 degrees Celsius. Do not freeze. Protect from light.

Formulations

• Inactivated poliovirus vaccine (IPV)
• Oral poliovirus vaccine (OPV)

Dosage

Children: Refer to specific drug information for paediatric dosing guidance.

Adults: Refer to specific drug information for dosing guidance.

Mechanism of action

The mechanism of action for drugs classified under types varies widely depending on the specific drug. Generally, they may function by inhibiting specific enzymes, blocking receptors, or modulating biological pathways to achieve their therapeutic effects.

Pharmacodynamics

Pharmacodynamics for types of drugs varies significantly depending on the specific medication. In general, pharmacodynamics describes the relationship between drug concentration and effect, including the drug's efficacy, potency, and duration of action. Common dynamics include receptor binding, post-receptor effects, and the drug's influence on physiological functions.

Pharmacokinetics

Pharmacokinetics involves the absorption, distribution, metabolism, and excretion (ADME) of drugs within the body. For various types of drugs, absorption may occur via oral, intravenous, or other routes, distribution is influenced by protein binding and tissue permeability, metabolism typically occurs in the liver, and excretion occurs primarily via renal pathways. Specific parameters such as half-life, bioavailability, and clearance rates depend on the particular drug type.

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.