TETGLOB

Indications

• Primary immunodeficiency disorders
• Secondary immunodeficiency (e.g. due to HIV infection)
• Chronic inflammatory demyelinating polyneuropathy (CIDP)
• Immune thrombocytopenic purpura (ITP)
• Kawasaki disease
• Prevention of infections in at-risk populations (e.g. following bone marrow transplant)

Dosage

Children: Refer to the BNF for Children for age-appropriate dosing guidelines; specific doses depend on the clinical condition and patient age.

Adults: Refer to specific guidelines for dosing based on indication; typically varies based on clinical scenario and patient condition.

Mechanism of action

Immunoglobulin exerts its effects primarily through the neutralization of pathogens and toxins, opsonization, and the activation of the complement system. It modulates immune responses by influencing the activity of various immune cells, including B cells, T cells, and macrophages, thereby enhancing antibody production and regulating inflammation.

Pharmacodynamics

The pharmacodynamics of immunoglobulin involve its ability to bind to specific antigens, effectively neutralizing them and facilitating their clearance. It also plays a crucial role in modulating the immune response, providing immediate passive immunity and promoting the establishment of active immunity over time. The diverse mechanisms through which immunoglobulin operates include antibody-dependent cell-mediated cytotoxicity (ADCC) and inhibition of pro-inflammatory cytokines.

Pharmacokinetics

Immunoglobulin is typically administered intravenously or subcutaneously. After administration, it is distributed throughout the extracellular space. The half-life of immunoglobulin varies but is generally in the range of 21 to 30 days, depending on the specific formulation and the patient's individual characteristics. It is primarily eliminated through the reticuloendothelial system, with catabolism occurring in various tissues.

Contra-indications

• Hypersensitivity to immunoglobulin preparations
• Selective IgA deficiency with a history of hypersensitivity
• Severe hyperprolinemia

Adverse effects

• Headache
• Nausea
• Fever
• Chills
• Fatigue
• Rash
• Anaphylactic reactions
• Thromboembolic events

Interactions

• Live attenuated vaccines may be less effective if administered concurrently with immunoglobulin therapy
• Caution is advised when administering with other blood products

Precautions

• Monitor for signs of anaphylaxis during and after administration
• Use with caution in patients with renal impairment
• Hydrate adequately to prevent renal dysfunction
• Consider the risk of thrombosis in patients with a history of thromboembolic events

Pregnancy

Immunoglobulin can be used during pregnancy if indicated, as it is considered safe based on available data.

Breast-feeding

Immunoglobulin is excreted in breast milk, but is generally considered safe during breastfeeding.

Storage

Store at 2-8 degrees Celsius. Do not freeze. Protect from light. Use before expiry date.

Formulations

• Intravenous immunoglobulin (IVIG)
• Subcutaneous immunoglobulin (SCIG)
• Intramuscular immunoglobulin (IMIG)

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