IMICEL INJECTION

Dosage

Children: Refer to specific product information for paediatric dosing guidelines as these will vary based on the anhydrous compound and its intended use.

Adults: Refer to specific product information for dosing guidelines as these will vary based on the anhydrous compound and its intended use.

Mechanism of action

The mechanism of action for anhydrous forms varies depending on the specific drug or compound involved. Generally, anhydrous compounds can improve absorption and bioavailability, as they may enhance solubility in gastrointestinal fluids. The absence of water can also lead to altered pharmacokinetics, affecting how the drug is distributed, metabolized, and excreted in the body.

Pharmacodynamics

Anhydrous forms typically exhibit pharmacodynamic properties that align with their hydrated counterparts but may show increased potency or faster onset of action due to improved solubility. This can result in enhanced therapeutic effects while potentially reducing the required dosage. The specific pharmacodynamics will depend on the individual compound and its interaction with biological targets.

Pharmacokinetics

Pharmacokinetics of anhydrous formulations can differ from their hydrated forms. They may have altered absorption rates due to increased solubility, leading to faster peak plasma concentrations. Distribution may be affected by the concentration and form of the anhydrous compound. Metabolism and excretion will also depend on the specific drug's characteristics but can be influenced by changes in solubility and bioavailability.

Pregnancy

There is limited data on the use of anhydrate during pregnancy. It should only be used if the potential benefits outweigh the risks.

Breast-feeding

The safety of anhydrate during breastfeeding has not been established. Caution is advised.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Indications

• Infection treatment with imipenem
• Prevention of renal toxicity associated with high doses of imipenem

Dosage

Children: Refer to the BNF for Children for appropriate pediatric dosing information.

Adults: Refer to the BNF for specific dosing guidelines as they may vary based on indication and patient factors.

Mechanism of action

Cilastatin inhibits the enzyme renal dehydropeptidase-I, which is responsible for the hydrolysis of imipenem in the renal tubules. This inhibition prevents the degradation of imipenem, allowing it to maintain its antimicrobial activity.

Pharmacodynamics

Cilastatin acts by blocking the action of renal dehydropeptidase, thereby protecting imipenem from being metabolized and increasing its renal excretion as unchanged drug. While cilastatin does not display any direct antibacterial activity, its role in preserving imipenem levels helps mitigate the risk of nephrotoxicity associated with high doses of imipenem.

Pharmacokinetics

The pharmacokinetics of cilastatin involves its administration alongside imipenem, with cilastatin enhancing the pharmacological profile of imipenem. Cilastatin is administered intravenously, and its half-life and metabolic pathways are closely tied to those of imipenem. The renal clearance of cilastatin is significant, and it plays a protective role against renal damage from imipenem.

Pregnancy

Cilastatin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. There are no adequate and well-controlled studies in pregnant women.

Breast-feeding

Cilastatin is excreted in human milk. Caution should be exercised when administering to breastfeeding women.

Storage

Store at room temperature, away from light and moisture. Do not freeze.

Formulations

• Cilastatin sodium for injection

Indications

• Severe bacterial infections
• Intra-abdominal infections
• Pneumonia
• Urinary tract infections
• Skin and soft tissue infections
• Bone and joint infections
• Meningitis

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines for paediatric patients, as doses vary based on age and weight.

Adults: The usual adult dose for imipenem ranges from 250 mg to 1 g administered intravenously every 6 to 8 hours, depending on the severity and type of infection.

Mechanism of action

Imipenem acts as an antimicrobial by inhibiting cell wall synthesis in various Gram-positive and Gram-negative bacteria. This mechanism is achieved through binding to penicillin-binding proteins (PBPs), particularly PBP-2, PBP-1a, and PBP-1b in E. coli and selected strains of Pseudomonas aeruginosa. The binding prevents the addition of peptidoglycan polymer to the bacterial cell wall, ultimately leading to cell lysis and death.

Pharmacodynamics

As a beta-lactam antibiotic, imipenem exhibits bactericidal properties by disrupting the synthesis of the bacterial cell wall. This activity is effective against a broad spectrum of pathogens, providing a crucial therapeutic option for serious infections, particularly those caused by resistant organisms.

Pharmacokinetics

Imipenem is typically administered intravenously due to its instability in acidic environments. It has a rapid distribution throughout the body, with peak plasma concentrations occurring shortly after administration. The drug is primarily excreted unchanged by the kidneys, and dose adjustments may be needed in patients with renal impairment. The half-life of imipenem is approximately 1 hour.

Contra-indications

• Hypersensitivity to imipenem or any of its components
• History of severe allergic reactions to other beta-lactam antibiotics

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Rash
• Seizures
• Superinfection
• Allergic reactions

Interactions

• Probenecid may increase plasma concentrations of imipenem
• Valproic acid may have decreased effectiveness when used with imipenem

Precautions

• Use with caution in patients with a history of seizures
• Assess renal function prior to use
• Monitor for signs of superinfection

Pregnancy

Use during pregnancy only if the potential benefit justifies the potential risk to the fetus, as there are no adequate and well-controlled studies in pregnant women.

Breast-feeding

Imipenem is excreted in breast milk, caution should be exercised when administering to nursing mothers.

Storage

Store in a cool, dry place, protected from light. Reconstituted solutions should be used promptly or stored in a refrigerator and discarded after 24 hours.

Formulations

• Powder for injection

Indications

• Surgical procedures
• Injection of medications
• Preparation of sterile pharmaceutical products
• Management of open wounds
• Use in controlled environments such as hospitals and laboratories

Dosage

Children: Refer to specific drug monographs for dosage information as sterile itself is not a pharmacological agent.

Adults: Refer to specific drug monographs for dosage information as sterile itself is not a pharmacological agent.

Mechanism of action

Sterility itself does not have a mechanism of action as it is a state of cleanliness and does not interact with biological systems. However, the methods used to achieve sterility, such as heat or chemical agents, act by denaturing proteins, disrupting cellular structures, or damaging nucleic acids in microorganisms, leading to their inactivation or destruction.

Pharmacodynamics

The pharmacodynamics of sterile techniques primarily involves the prevention of microbial infection and contamination when administering medications. By ensuring that products are sterile, the risk of adverse effects related to infections is minimized. The effectiveness of sterilization methods can be influenced by factors such as temperature, duration of exposure, and the type of microorganisms present.

Pharmacokinetics

As sterility does not pertain to a specific drug, pharmacokinetics is not applicable. However, the pharmacokinetics of a drug will depend on its formulation, route of administration, and the presence of preservatives or stabilizers that may be used alongside sterile preparations.

Pregnancy

Sterile preparations are generally considered safe during pregnancy as they are used to provide hydration, nutrition, or medications in a controlled manner, but specific formulations should be assessed individually.

Breast-feeding

Sterile solutions used for hydration or nutritional support are typically safe during breastfeeding, but any specific additives or medications within the solutions should be evaluated for safety.

Storage

Sterile solutions should be stored in a cool, dry place, protected from light, and should be used before the expiration date. Once opened, they may have specific storage requirements based on the formulation.

Formulations

• Sterile saline solution
• Sterile water for injection
• Sterile dextrose solution
• Sterile electrolyte solutions

Mechanism of action

Cilastatin is a renal dehydropeptidase-I inhibitor. Since the antibiotic, imipenem, is hydrolyzed by dehydropeptidase-I, which resides in the brush border of the renal tubule, cilastatin is administered with imipenem to block the metabolism of imipenem.

Pharmacodynamics

Cilastatin is a chemical compound which inhibits the human enzyme dehydropeptidase. Renal Dehydropeptidase degrades the antibiotic [imipenem]. Cilastatin is therefore combined intravenously with imipenem in order to protect it from dehydropeptidase and prolong its antibacterial effect. However, cilastatin in and of itself does not have any antibacterial activity. The increased renal excretion of unchanged imipenem appears to prevent proximal tubular necrosis associated with high doses of imipenem.

Mechanism of action

Imipenem acts as an antimicrobial through the inhibition of cell wall synthesis of various gram-positive and gram-negative bacteria. This inhibition of cell wall synthesis in gram-negative bateria is attained by binding to penicillin-binding proteins (PBPs). In E. coli and selected strains of P. aeruginosa, imipenem has shown to have the highest affinity to PBP-2, PBP-1a, and PBP-1b. This inhibition of PBPs prevents the bacterial cell from adding to the peptidoglycan polymer which forms the bacterial cell wall eventually leading to cell death.

Pharmacodynamics

Imipenem is a beta-lactam antibiotic belongings to the subgroup of carbapenems. Imipenem is active against aerobic and anaerobic Gram positive as well as Gram negative bacteria including <i>Pseudomonas aeruginosa</i> and the <i>Enterococcus</i>. It exerts a bactericidal effects by disrupting cell wall synthesis.