EPIAO

Indications

• Hypoalbuminemia
• Volume resuscitation in shock
• Liver cirrhosis
• Nephrotic syndrome
• Burns
• Postoperative fluid management

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations based on clinical condition and patient response.

Adults: Refer to the appropriate guidelines for specific dosing recommendations based on clinical condition and patient response.

Mechanism of action

Albumin acts by maintaining oncotic pressure in the vascular system, thus preventing fluid from leaking into tissues and promoting the return of interstitial fluid to the bloodstream. This action helps restore blood volume and improve circulation in patients with conditions that lead to hypovolemia or edema. Additionally, albumin can bind and transport various endogenous and exogenous substances, influencing their distribution and elimination.

Pharmacodynamics

The primary pharmacodynamic effect of albumin is the increase in plasma oncotic pressure, which helps to retain fluid within the vascular space. This effect is critical in managing conditions associated with fluid imbalance. Albumin also has antioxidant properties and may play a role in modulating inflammatory responses, although these effects are secondary to its role in volume expansion.

Pharmacokinetics

Albumin is administered intravenously, where it is distributed rapidly throughout the vascular compartment. The half-life of albumin in circulation is typically around 15 to 20 days, depending on physiological conditions. It is metabolized primarily in the liver, with a small percentage undergoing renal clearance. The distribution volume is influenced by factors such as hydration status and the presence of diseases affecting protein levels.

Contra-indications

• Severe anemia
• Congestive heart failure
• Pulmonary edema
• Severe dehydration
• Allergy to albumin or any component of the formulation

Adverse effects

• Allergic reactions including anaphylaxis
• Headache
• Nausea
• Vomiting
• Fever
• Hypotension
• Fluid overload

Interactions

• Caution should be exercised when administering with other fluids or medications that may affect fluid balance
• May alter the pharmacokinetics of certain drugs due to changes in plasma volume

Precautions

• Monitor for signs of fluid overload, especially in patients with heart or kidney disease
• Use cautiously in patients with a history of allergic reactions
• Ensure proper storage and handling to avoid contamination

Pregnancy

Albumin is generally considered safe during pregnancy when administered for appropriate indications, but its use should be assessed on a case-by-case basis.

Breast-feeding

Albumin can be used during breastfeeding, as it is a naturally occurring protein in human milk.

Storage

Store at 2 to 8 degrees Celsius. Do not freeze. Protect from light and use within the expiry date.

Formulations

• Human albumin solution (various concentrations)
• Albumin (500 mL bags, 20% and 5% solutions)

Indications

• Acidulant in food and beverages
• Preservative in pharmaceutical formulations
• pH adjuster in various chemical preparations

Dosage

Children: Refer to product-specific guidelines for appropriate dosing based on formulation and indication.

Adults: Refer to product-specific guidelines for appropriate dosing based on formulation and indication.

Mechanism of action

Citric acid acts by chelating metal ions, which can enhance the solubility of certain compounds and improve their bioavailability. It also contributes to the acidity of the environment, which can influence enzymatic activity and metabolic pathways, particularly in the degradation of citronellol.

Pharmacodynamics

Citric acid exhibits mild pharmacological effects primarily attributed to its role in metabolic processes. It aids in the regulation of pH levels, which can impact enzymatic reactions and biochemical pathways. The acid's chelating properties may help to reduce the toxicity of certain metal ions in biological systems.

Pharmacokinetics

Citric acid is rapidly absorbed after oral administration and is metabolized in the liver. It undergoes conversion to various metabolites in the citric acid cycle, contributing to energy production. The elimination primarily occurs through urine, with minimal accumulation in the body.

Pregnancy

Citric acid is generally regarded as safe during pregnancy when used in food amounts. However, consult a healthcare provider for advice on medicinal use.

Breast-feeding

Citric acid is considered safe during breastfeeding when consumed in food amounts. For medicinal use, consult a healthcare provider.

Storage

Store in a cool, dry place away from direct sunlight.

Indications

• Anemia associated with chronic renal failure
• Anemia in patients undergoing chemotherapy

Mechanism of action

Erythropoietin binds to the erythropoietin receptor (EPO-R) on erythroid progenitor cells, activating intracellular signaling pathways, particularly the JAK2/STAT5 pathway. This binding induces a conformational change in EPO-R, activating JAK2 through phosphorylation. Activated JAK2 then phosphorylates tyrosine residues in the EPO-R cytoplasmic domain, serving as docking sites for signaling proteins, including phosphorylated STAT5. Once activated, STAT5 translocates to the nucleus, functioning as a transcription factor to stimulate genes that promote cell division and inhibit apoptosis, critical for erythroid differentiation.

Pharmacodynamics

Erythropoietin regulates erythrocyte differentiation and maintains physiological levels of circulating erythrocyte mass. It increases the reticulocyte count within 10 days of administration, followed by increases in RBC count, hemoglobin, and hematocrit within 2 to 6 weeks. In patients undergoing hemodialysis, doses exceeding 300 Units/kg three times weekly do not yield a greater biological response. Erythropoietin effectively stimulates erythropoiesis in patients with chronic renal failure and has also demonstrated efficacy in anemic patients receiving zidovudine for HIV and those undergoing chemotherapy.

Pharmacokinetics

Erythropoietin is administered via subcutaneous or intravenous routes. It has a half-life of approximately 4 to 13 hours, depending on the route of administration and the patient's condition. The onset of action is typically within days, with peak effects seen in 2 to 6 weeks. Renal function significantly affects its clearance, necessitating dosage adjustments in patients with renal impairment.

Contra-indications

• Uncontrolled hypertension
• Pure red cell aplasia following erythropoietin therapy
• Hypersensitivity to the active substance or any of the excipients

Adverse effects

• Hypertension
• Thrombotic events (e.g., stroke, myocardial infarction)
• Headache
• Fatigue
• Nausea
• Injection site reactions
• Seizures
• Allergic reactions

Interactions

• Antineoplastic agents may have an additive effect on blood pressure
• Iron supplements should be monitored as erythropoietin increases erythropoiesis and may require increased iron availability

Precautions

• Monitor blood pressure regularly during treatment
• Assess iron status before and during therapy
• Use with caution in patients with a history of seizures
• Caution in patients with a history of thromboembolic events

Pregnancy

Erythropoietin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Limited data are available.

Breast-feeding

Erythropoietin is excreted in human milk; caution should be exercised when administered to nursing women.

Storage

Store in a refrigerator (2°C to 8°C). Do not freeze. Protect from light.

Formulations

• Injection solution in vials or pre-filled syringes containing epoetin alfa

Dosage

Children: Dosage for human-derived biological products in pediatrics should be determined based on specific product guidelines and the clinical context.

Adults: Dosage for human-derived biological products varies widely. Refer to specific product information for appropriate dosing.

Mechanism of action

Human physiology is governed by complex biological systems involving various cellular and molecular pathways. The mechanisms of action for human-derived biological products vary widely depending on the specific context, including immune response, hormonal regulation, and metabolic processes.

Pharmacodynamics

Pharmacodynamics in humans involves the interaction of drugs with biological systems, resulting in therapeutic effects. This includes receptor binding, signal transduction, and physiological responses. The effects are influenced by genetic factors, existing health conditions, and concurrent medications.

Pharmacokinetics

Pharmacokinetics in humans involves the absorption, distribution, metabolism, and excretion (ADME) of substances. Factors such as age, sex, body weight, and organ function can significantly influence these processes. Drug absorption may occur via oral, intravenous, or other routes, while distribution depends on blood flow and tissue permeability. Metabolism typically occurs in the liver, and excretion primarily takes place through the kidneys.

Pregnancy

There is no specific information available; consult local guidelines.

Breast-feeding

There is no specific information available; consult local guidelines.

Storage

Store in a cool, dry place away from direct sunlight.

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

Mechanism of action

Erythropoietin or exogenous epoetin alfa binds to the erythropoietin receptor (EPO-R) and activates intracellular signal transduction pathways. The affinity (Kd) of EPO for its receptor on human cells is ∼100 to 200 pM. Upon binding to EPO-R on the surface of erythroid progenitor cells, a conformational change is induced which brings EPO-R-associated Janus family tyrosine protein kinase 2 (JAK2) molecules into close proximity. JAK2 molecules are subsequently activated via phosphorylation, then phosphorylate tyrosine residues in the cytoplasmic domain of the EPO-R that serve as docking sites for Src homology 2-domain-containing intracellular signaling proteins. The signalling proteins include STAT5 that once phosphorylated by JAK2, dissociates from the EPO-R, dimerizes, and translocates to the nucleus where they serve as transcription factors to activate target genes involved in cell division or differentiation, including the apoptosis inhibitor Bcl-x. The inhibition of apoptosis by the EPO-activated JAK2/STAT5/Bcl-x pathway is critical in erythroid differentiation. Via JAK2-mediated tyrosine phosphorylation, erythropoietin and epoetin alfa also activates other intracellular proteins involved in erythroid cell proliferation and survival, such as Shc , phosphatidylinositol 3-kinase (PI3K), and phospholipase C-γ1. Epoetin alfa is a glycoprotein, produced by recombinant DNA technology, that contains 165 amino acids in a sequence identical to that of endogenous human erythropoietin. Recombinant epoetin has the same biological activity as the endogenous hormone, which induces erythropoiesis by stimulating the division and differentiation of committed erythroid progenitor cells, including burst-forming units-erythroid, colony-forming units- erythroid, erythroblasts, and reticulocytes, in bone marrow. Erythropoietin also induces the release of reticulocytes from the bone marrow into the blood stream, where they mature into erythrocytes. Endogenous erythropoietin is produced primarily in the kidney. The anemia associated with chronic renal failure is caused primarily by inadequate production of the hormone. Administration of epoetin corrects the erythropoietin deficiency in patients with chronic renal failure. Epoetin also stimulates red blood cell production in patients who do not have a documented erythropoietin deficiency, i.e., patients with normal or slightly elevated concentrations of endogenous erythropoietin. However, it may not be effective in patients who are anemic despite having significantly elevated concentrations of erythropoietin.

Pharmacodynamics

Erythropoietin and epoetin alfa are involved in the regulation of erythrocyte differentiation and the maintenance of a physiological level of circulating erythrocyte mass. It is reported to increase the reticulocyte count within 10 days of initiation, followed by increases in the RBC count, hemoglobin, and hematocrit, usually within 2 to 6 weeks. Depending on the dose administered, the rate of hemoglobin increase may vary. In patients receiving hemodialysis, a greater biologic response is not observed at doses exceeding 300 Units/kg 3 times weekly. Epoetin alfa serves to restore erythropoietin deficiency in pathological and other clinical conditions where normal production of erythropoietin is impaired or compromised. In anemic patients with chronic renal failure (CRF), administration with epoetin alfa stimulated erythropoiesis by increasing the reticulocyte count within 10 days, followed by increases in the red cell count, hemoglobin, and hematocrit, usually within 2 to 6 weeks. Epoetin alfa was shown to be effective in increasing hematocrit in zidovudine-treated HIV-infected patients and anemic cancer patients undergoing chemotherapy.