ALS-SVAS (SNAKE VENOM ANTI SERUM 1ML/20LD50 & 1ML/25LD50)(AFRICAN) LYOPHILIZED POWDER FOR INJECTION

Indications

• Primary immunodeficiency disorders
• Secondary immunodeficiency states
• Autoimmune diseases such as Guillain-Barré syndrome
• Certain infections including viral hepatitis
• Prevention of infections in immunocompromised patients

Dosage

Children: Refer to the BNF for Children for appropriate dosing information tailored to paediatric patients.

Adults: Refer to the BNF for specific dosing information as it varies based on the condition being treated.

Mechanism of action

Immunoglobulins work by binding to specific antigens on pathogens, marking them for destruction by other immune cells. This can involve neutralization of toxins, opsonization for phagocytosis, and activation of the complement system, leading to enhanced clearance of pathogens and modulation of immune responses.

Pharmacodynamics

The pharmacodynamics of immunoglobulins are characterized by their ability to modulate immune responses. They can enhance the activity of phagocytic cells, inhibit the proliferation of certain cells in the immune system, and alter the production of cytokines. The specific effects depend on the subclass of immunoglobulin and the nature of the disease being treated.

Pharmacokinetics

Immunoglobulins are typically administered intravenously or subcutaneously. They have a half-life that can vary widely depending on the specific product, ranging from several days to weeks. After administration, they distribute throughout the body, with a significant portion remaining in the vascular compartment. Metabolism occurs primarily through proteolytic degradation and clearance by the reticuloendothelial system.

Interactions

• antifungals, azoles + acalabrutinib: Severe (increases exposure)
• dronedarone + antipsychotics, second generation: Severe (increases exposure)
• mexiletine + antiarrhythmics: Severe (increases risk of torsade de pointes)
• mitotane + antiarrhythmics: Severe (decreases exposure)
• carbamazepine + antipsychotics, second generation: Severe (increases risk of myelosuppression)
• antiepileptics (carbamazepine, fosphenytoin, phenobarbital, phenytoin, primidone) + elexacaftor: Severe (decreases exposure)
• antiepileptics (carbamazepine, fosphenytoin, oxcarbazepine, phenobarbital, phenytoin, primidone) + imatinib: Severe (decreases exposure)
• iron chelators + antiepileptics: Severe (decreases absorption)
• lumacaftor + antiepileptics: Severe (decreases exposure)
• antiepileptics (fosphenytoin, phenobarbital, phenytoin, primidone) + metyrapone: Severe (decreases effects)

Indications

• Diagnostic blood tests
• Assessment of organ function
• Evaluation of electrolyte balance
• Monitoring of therapeutic drug levels
• Detection of antibodies or infectious agents

Dosage

Children: Dosage is not applicable as serum is a biological fluid used for diagnostic purposes and not an administered drug.

Adults: Dosage is not applicable as serum is a biological fluid used for diagnostic purposes and not an administered drug.

Mechanism of action

Serum itself does not have a specific mechanism of action as it is a biological fluid. However, its components, particularly proteins such as albumin and immunoglobulins, contribute to homeostasis, transport, and immune response. Albumin helps in maintaining oncotic pressure and transporting various substances, while immunoglobulins play a vital role in the immune response.

Pharmacodynamics

The pharmacodynamics of serum are closely related to its composition. The proteins in serum, including enzymes, hormones, and antibodies, exert various physiological effects. For example, serum albumin helps maintain blood volume and pressure, while globulins are involved in immune function. Changes in serum composition can affect the pharmacodynamics of drugs, influencing their distribution, metabolism, and elimination.

Pharmacokinetics

Serum does not follow a traditional pharmacokinetic profile, as it is a complex mixture rather than a single drug. However, the elimination and distribution of substances within the serum can be influenced by factors such as protein binding, blood flow, and the physiological state of the individual. The half-life of any drugs or substances present in serum will depend on their specific characteristics and interactions with serum components.

Adverse effects

• Allergic reactions
• Infection at the injection site
• Fever
• Rash
• Joint pain

Precautions

• Use with caution in individuals with a history of allergic reactions
• Monitor for signs of infection
• Assess for any history of autoimmune conditions

Pregnancy

Consult healthcare provider. Safety in pregnancy is not well established.

Breast-feeding

Consult healthcare provider. Limited information is available regarding excretion in breast milk.

Storage

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

Formulations

• Intravenous solution
• Subcutaneous injection

Indications

• Snake bites
• Envenomation
• Antivenom therapy
• Supportive care for systemic effects

Dosage

Children: For snake bites in children, refer to specific antivenom guidelines and local protocols. Dosing is typically adjusted based on weight and severity of envenomation.

Adults: For snake bites, refer to specific antivenom guidelines and local protocols. Dosing varies based on the type of snake, severity of envenomation, and clinical presentation.

Mechanism of action

The mechanisms of action of snake venom components vary widely. Neurotoxins interfere with neurotransmission by blocking acetylcholine receptors at the neuromuscular junction, leading to paralysis. Hemotoxins can disrupt blood coagulation pathways and damage blood vessels, causing hemorrhage and tissue necrosis. Cytotoxins can cause direct damage to cells and tissues, leading to pain and inflammation.

Pharmacodynamics

The pharmacodynamics of snake venom is characterized by its ability to interact with specific biological targets in the body, leading to a range of toxic effects. For example, neurotoxins can cause rapid onset of muscle paralysis, while hemotoxins can lead to bleeding and organ dysfunction. The effects depend on the dose, route of exposure, and individual susceptibility. The toxicity of snake venom can vary greatly between different species and individual snakes.

Pharmacokinetics

The pharmacokinetics of snake venom is not well characterized due to its complex nature and variability. Generally, venom components are rapidly absorbed into the bloodstream following envenomation. Distribution occurs systemically, affecting various tissues and organs. Metabolism can involve enzymatic breakdown by host tissues, while excretion pathways are not well defined. Severity of symptoms and toxicity can depend on the specific components of the venom and the patient's health status.

Adverse effects

• Local tissue necrosis
• Allergic reactions
• Systemic reactions
• Hemolysis
• Coagulation disorders

Precautions

• Use with caution in individuals with a history of allergic reactions to snake venom
• Monitor for signs of severe allergic reactions
• Assess local tissue condition after envenomation

Pregnancy

Safety during pregnancy is not established; use only if the benefits outweigh risks.

Breast-feeding

Safety during breastfeeding is not established; consult healthcare providers.

Storage

Store in a cool, dry place away from direct sunlight. Specific storage conditions may vary based on formulation.

Mechanism of action

Venoms exert their effects through various mechanisms, including enzymatic activity that disrupts cellular integrity, inhibition of neurotransmitter release, and modulation of ion channels. For example, neurotoxic venoms may block acetylcholine receptors at neuromuscular junctions, leading to paralysis. Other venoms can activate or inhibit specific receptors or pathways, resulting in pain, inflammation, or coagulation disturbances.

Pharmacodynamics

The pharmacodynamics of venom components depend on their specific targets and effects. Many venoms are designed to incapacitate prey quickly, with rapid onset of action. Effects may include paralysis, hemorrhage, or disruption of normal physiological functions. The potency and duration of action vary widely among different venoms and their constituent molecules.

Pharmacokinetics

Pharmacokinetics of venom components can vary significantly based on their structure and the route of exposure. After envenomation, the compounds may be rapidly absorbed into the bloodstream, leading to systemic effects. Metabolism typically occurs in the liver, and excretion can happen through urine or feces. The onset of action can be immediate, while the duration depends on the specific venom type and individual response.

Pregnancy

There is limited information on the use of venom during pregnancy. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Caution is advised when using venom while breastfeeding due to the unknown effects on the infant.

Storage

Store in a cool, dry place, away from direct sunlight. Specific storage conditions may vary depending on the formulation.