BETT

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

• Diphtheria prophylaxis
• Tetanus prophylaxis
• Pertussis prophylaxis (when combined with other vaccines)

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations for pediatric immunization with toxoids.

Adults: Refer to specific guidelines for each toxoid vaccine, as dosing may vary based on the type of vaccine and individual patient factors.

Mechanism of action

Toxoids work by stimulating the immune system to produce antibodies against the toxin without causing disease. When administered, the immune system recognizes the toxoid as a foreign substance and generates a specific immune response. This includes the production of immunoglobulin G (IgG) antibodies that can neutralize the active toxin if the individual is exposed to the bacteria in the future.

Pharmacodynamics

The pharmacodynamics of toxoids involve the activation of the adaptive immune response. After vaccination, dendritic cells present the antigen to T cells, which then help B cells differentiate into plasma cells that produce specific antibodies. The presence of these antibodies provides immunity against the toxin by neutralizing its effects, thereby preventing the disease associated with the original bacterial toxin.

Pharmacokinetics

Toxoids are typically administered via intramuscular or subcutaneous injection. Following administration, they are gradually taken up by antigen-presenting cells, which then process and present the toxoid to T cells. The immunogenic response can develop over several weeks. The duration of immunity can vary, necessitating booster doses to maintain adequate antibody levels over time.

Adverse effects

• Local reactions at the injection site, such as pain, swelling, or redness.
• Fever.
• Fatigue.
• Headache.
• Allergic reactions in rare cases.

Precautions

• Use with caution in individuals with a history of severe allergic reactions to a vaccine component.
• Monitor patients for allergic reactions post-vaccination.

Pregnancy

Toxoids are generally considered safe during pregnancy; however, consultation with a healthcare provider is recommended.

Breast-feeding

Toxoids are considered safe for use during breastfeeding.

Storage

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

Formulations

• Diphtheria toxoid
• Tetanus toxoid
• Pertussis toxoid