POLIO SABIN ONE AND THREE (ORAL)

Indications

• Moderate to severe pain management
• Chronic pain conditions
• Palliative care
• Cancer pain management

Dosage

Children: Refer to the BNF for Children for appropriate paediatric dosing recommendations.

Adults: Refer to specific medical guidelines for dosing, as individual patient factors must be considered.

Mechanism of action

Levorphanol acts primarily as a mu-opioid receptor agonist, which leads to the inhibition of ascending pain pathways in the central nervous system. This action alters the perception of and response to pain. Additionally, levorphanol has some interaction with kappa and delta opioid receptors, contributing to its analgesic effects. It also inhibits the reuptake of norepinephrine and serotonin, which may enhance its pain-relieving properties.

Pharmacodynamics

The analgesic effects of levorphanol are dose-dependent and are characterized by a rapid onset of action and a relatively long duration of effect compared to other opioids. It can cause significant sedation, respiratory depression, and potential for dependence and tolerance with prolonged use. Levorphanol may also cause side effects such as constipation and nausea, typical of opioid medications.

Pharmacokinetics

Levorphanol is well-absorbed after oral administration, with a bioavailability of approximately 90%. It undergoes extensive hepatic metabolism, and its metabolites are primarily excreted via the kidneys. The half-life of levorphanol is approximately 9-12 hours, allowing for dosing every 6-12 hours depending on the clinical situation. The drug's pharmacokinetics can be influenced by factors such as liver function and concomitant medications.

Pregnancy

Consult with a healthcare provider for risk assessment as data on safety during pregnancy is limited.

Breast-feeding

Consult with a healthcare provider as it is not clear if this drug passes into breast milk.

Storage

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

Indications

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

Dosage

Children: Refer to the BNF for Children for appropriate dosing schedules and recommendations for poliovirus vaccination in children.

Adults: Refer to specific guidelines for IPV and OPV administration in adults, as vaccination schedules may vary based on age and immunization history.

Mechanism of action

Poliovirus primarily infects the motor neurons of the spinal cord and brainstem, leading to cell lysis and apoptosis. The viral replication occurs in the cytoplasm of the host cells, resulting in the release of new virions. The immune response triggered by the infection can lead to paralysis due to damage to the motor neurons.

Pharmacodynamics

The pharmacodynamics of polio vaccines involve the induction of an immune response against the poliovirus. The IPV induces serum neutralizing antibodies, while the OPV induces both serum and mucosal immunity. This immune response prevents the establishment of infection and protects against the disease.

Pharmacokinetics

Poliovirus vaccines do not have a pharmacokinetic profile in the traditional sense, as they are biological products. However, the IPV is administered intramuscularly, leading to systemic absorption and subsequent immunogenicity. The OPV is administered orally, leading to replication in the gastrointestinal tract and inducing both humoral and cellular immunity.

Contra-indications

• Severe allergic reaction to polio vaccine components
• Immunocompromised state (inactivated vaccine preferred)

Adverse effects

• Injection site reactions (pain, swelling, redness)
• Fever
• Fatigue
• Gastrointestinal disturbances (nausea, vomiting)
• Rarely, vaccine-derived paralytic poliomyelitis

Interactions

• Live vaccines may be affected by immunosuppressive therapies
• Concurrent administration with other vaccines is generally safe but consult vaccination guidelines

Precautions

• History of allergic reactions
• Patients with a history of Guillain-Barré syndrome
• Caution in patients with neurological disorders

Pregnancy

Polio vaccination is recommended during pregnancy if the woman is at risk of exposure, as the benefits outweigh potential risks.

Breast-feeding

Polio vaccine can be administered to breastfeeding mothers without risk to the infant.

Storage

Store at 2-8°C. Do not freeze. Protect from light.

Formulations

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

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.

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.