DIPHTHERIA AND TETANUS VACCINE (ADSORBED, REDUCED ANTIGEN(S) CONTENT)-10 DOSE

Indications

• Prevention of diphtheria through vaccination
• Treatment of diphtheria infection
• Management of respiratory obstruction due to pseudomembrane

Dosage

Children: Refer to specific

Adults: Refer to specific guidelines for the treatment of diphtheria. Antitoxin and antibiotics are typically used in treatment.

Mechanism of action

The pathogenicity of Corynebacterium diphtheriae is largely due to its production of diphtheria toxin, an A-B toxin that inhibits protein synthesis in host cells. The toxin is composed of two subunits: the A subunit, which enters the cytoplasm of the cell and catalyzes the ADP-ribosylation of elongation factor 2 (EF-2), leading to cell death, and the B subunit, which binds to the cell surface receptor, facilitating the entry of the A subunit. This results in local tissue damage and systemic effects, including myocarditis and neuropathy.

Pharmacodynamics

Diphtheria toxin exerts its effects primarily through inhibiting protein synthesis, causing cell death in susceptible tissues. The resulting necrosis can lead to the characteristic pseudomembrane formation in the throat and can affect other organs, including the heart and nervous system. The immune response to the toxin and the bacteria provides some level of protection, which is the basis for vaccination strategies.

Pharmacokinetics

The pharmacokinetics of the diphtheria toxin itself are not typically described in terms of absorption, distribution, metabolism, and excretion, as it is a potent toxin rather than a conventional drug. However, the body’s immune response to the toxin is crucial for recovery. After vaccination, the body generates antibodies against the toxin, which can neutralize its effects upon exposure to the bacterium.

Pregnancy

Diphtheria vaccination is recommended during pregnancy to protect the mother and fetus. The vaccine is inactivated and poses no risk.

Breast-feeding

Diphtheria vaccination is safe during breastfeeding. Antibodies may be transferred to the infant through breast milk.

Storage

Store in a refrigerator at 2-8 degrees Celsius. Do not freeze.

Formulations

• Diphtheria toxoid vaccine

Indications

• Clinical term 1
• Common term 1
• Clinical term 2
• Common term 2

Dosage

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

Adults: Refer to the BNF for specific adult dosing guidelines.

Mechanism of action

Dose acts by modulating the activity of specific neurotransmitter receptors and ion channels, influencing various physiological pathways. Its precise mechanism may involve interactions with G-protein coupled receptors, leading to downstream signaling effects that impact cellular responses.

Pharmacodynamics

Dose exhibits a range of effects depending on the dosage and target tissues. It is known to alter neurotransmitter release, affect ion conductance, and influence metabolic pathways, thereby contributing to its therapeutic efficacy and potential side effects.

Pharmacokinetics

Dose is generally absorbed following administration, with peak plasma concentrations occurring within a specified timeframe. Its distribution is influenced by tissue binding and permeability across cell membranes. The drug is metabolized primarily in the liver, with metabolites being excreted via renal and biliary routes. The half-life can vary based on individual patient factors, including age, liver function, and other concurrent medications.

Indications

• Tetanus prophylaxis
• Treatment of tetanus infection
• Management of tetanus symptoms

Dosage

Children: Refer to the specific guidelines for tetanus immunoglobulin and other supportive treatments as per clinical protocols.

Adults: Refer to the specific guidelines for tetanus immunoglobulin and other supportive treatments as per clinical protocols.

Mechanism of action

The tetanus toxin binds to the presynaptic membrane of motor neurons and is transported retrogradely to the spinal cord, where it interferes with neurotransmitter release, particularly inhibiting the release of glycine and gamma-aminobutyric acid (GABA), leading to unopposed motor neuron activity and resultant muscle rigidity and spasms.

Pharmacodynamics

Tetanus toxin is one of the most potent toxins known, with effects that can manifest within hours of exposure. The toxin's ability to block inhibitory neurotransmitter release results in a state of continuous muscle contraction, known as tetany. The clinical presentation of tetanus includes trismus (lockjaw), muscle rigidity, and autonomic instability, among others.

Pharmacokinetics

The pharmacokinetics of tetanus toxin are complex due to its high potency and the nature of its action. Following entry into the body, the toxin binds to nerve endings and is internalized, leading to its effects on neurotransmitter release. The half-life of the toxin is not well defined as it does not circulate freely in the bloodstream but acts locally at the neuromuscular junction. Recovery from the effects of the toxin may take weeks to months, depending on the severity of the infection and the treatment provided.

Adverse effects

• Pain at the injection site
• Fever
• Fatigue
• Headache
• Nausea

Precautions

• Ensure patient is up to date with vaccinations
• Monitor for allergic reactions post-vaccination
• Consider history of neurological disorders

Pregnancy

Tetanus vaccination is considered safe during pregnancy and is recommended to protect both the mother and the newborn.

Breast-feeding

Tetanus vaccination is safe during breastfeeding and does not affect the nursing infant.

Storage

Store in a refrigerator at 2–8 degrees Celsius. Do not freeze.

Formulations

• Tetanus toxoid vaccine

Indications

• Prevention of infectious diseases such as measles, mumps, rubella, hepatitis B, influenza, and human papillomavirus (HPV)
• Travel vaccinations for diseases endemic to certain regions
• Vaccination for at-risk populations, such as those with compromised immune systems or specific occupational exposures

Dosage

Children: Dosage varies by vaccine type and age; refer to the BNF for Children for specific dosing information.

Adults: Dosage varies by vaccine type and indication; refer to specific guidelines for each vaccine.

Mechanism of action

Vaccines work by mimicking an infection. They introduce a harmless component of a pathogen (antigen) to the immune system, prompting the body to produce an immune response. This includes the generation of antibodies and memory cells that provide long-term immunity. Upon subsequent exposure to the actual pathogen, the immune system is primed to respond more rapidly and effectively.

Pharmacodynamics

The pharmacodynamics of vaccines involves the activation of both humoral and cellular immunity. Vaccines stimulate B cells to produce antibodies against the pathogen, while T cells are activated to destroy infected cells. This dual response helps to establish immunological memory, which enables a faster and more robust response upon re-exposure to the pathogen.

Pharmacokinetics

Vaccines are administered via various routes, including intramuscular, subcutaneous, and oral. After administration, the antigens are presented to antigen-presenting cells, which activate T cells and stimulate B cell proliferation and differentiation. The half-life of vaccine-induced immunity varies depending on the type of vaccine, with some providing lifelong immunity and others requiring booster doses to maintain protection.

Contra-indications

• Severe allergic reaction (anaphylaxis) to a component of the vaccine
• Severe immunocompromised state for live attenuated vaccines

Adverse effects

• Local reactions at the injection site (pain, redness, swelling)
• Fever
• Fatigue
• Headache
• Muscle pain
• Joint pain
• Nausea

Interactions

• Immunosuppressive medications may reduce vaccine efficacy
• Concurrent administration of some vaccines may require spacing to optimize immune response

Precautions

• History of allergic reactions to vaccines or vaccine components
• Pregnancy (specific vaccines may be contraindicated)
• Moderate to severe acute illness with or without fever

Pregnancy

Consult healthcare provider. Some vaccines are contraindicated during pregnancy, while others are recommended.

Breast-feeding

Generally considered safe, but consult healthcare provider regarding specific vaccines.

Storage

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

Formulations

• Liquid suspension for injection
• Lyophilized powder for reconstitution