Drez powder

Indications

• Computed tomography (CT) imaging
• Angiography
• Fluoroscopy
• Intravenous urograms
• Cholangiography

Dosage

Children: Paediatric dosing depends on the child's age, weight, and the specific procedure being performed. Consult the BNF for Children for appropriate dosing recommendations.

Adults: Dosage varies based on the specific iodinated contrast agent used and the type of procedure. Refer to specific product guidelines for detailed dosing information.

Mechanism of action

Iodinated contrast agents work by increasing the absorption of X-rays, due to the high atomic number of iodine, which is significantly greater than that of soft tissues. When introduced into the body, these agents help to delineate vascular structures and organs, allowing for improved visualization in imaging studies.

Pharmacodynamics

The pharmacodynamics of iodinated contrast agents are characterized by their ability to alter the radiographic density of tissues. They enhance the contrast between different tissues, especially in vascular structures, by providing a stark difference in X-ray attenuation. The pharmacological effects are largely dose-dependent, influencing the quality of imaging results and the safety profile in patients.

Pharmacokinetics

Iodinated contrast agents are typically administered intravenously. Their distribution in the body is rapid, with peak plasma concentrations occurring soon after administration. The agents are primarily eliminated through renal excretion, with a significant portion excreted unchanged in urine within 24 hours. The half-life can vary depending on the specific agent used and the patient's renal function.

Adverse effects

• Hypersensitivity reactions
• Nausea
• Vomiting
• Thyroid dysfunction
• Nephrotoxicity
• Extravasation injury

Interactions

• May interact with anticoagulants, increasing the risk of bleeding
• May affect thyroid function tests
• Concurrent use with nephrotoxic agents may increase risk of renal impairment

Precautions

• Use with caution in patients with a history of thyroid disease
• Monitor renal function prior to administration, especially in patients with pre-existing renal impairment
• Ensure adequate hydration to reduce the risk of nephrotoxicity

Pregnancy

Iodinated contrast agents should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. They should be avoided in the first trimester if possible.

Breast-feeding

Iodinated contrast agents are generally considered safe for use during breastfeeding, but mothers should be advised to monitor their infants for any signs of adverse reactions.

Storage

Store at room temperature, protect from light, and keep away from moisture. Check expiry date before use.

Formulations

• Iodinated contrast medium for intravenous use
• Iodinated contrast medium for intra-arterial use
• Iodinated contrast medium for oral administration

Indications

• Topical antiseptic for skin disinfection
• Surgical scrubs and hand sanitizers
• Wound care management
• Pharmaceutical excipient in solid and liquid formulations

Dosage

Children: Refer to specific product guidelines for pediatric dosing recommendations, as doses can vary based on formulation and intended use.

Adults: Refer to specific product guidelines for dosing recommendations, as doses can vary based on the formulation and intended use.

Mechanism of action

Povidone acts by forming a complex with iodine when used as an antiseptic, which releases iodine slowly to exert its antimicrobial effect. The iodine disrupts microbial cell walls and interferes with protein synthesis, leading to cell death. Additionally, as a polymer, povidone can enhance drug solubility and stability by forming a hydrophilic matrix.

Pharmacodynamics

Povidone has a broad spectrum of antimicrobial activity against bacteria, viruses, and fungi. Its antiseptic properties are primarily due to the release of iodine, which is effective in reducing microbial load and preventing infection. The polymer's ability to bind to various substances allows it to be utilized in formulations that require improved stability and solubility.

Pharmacokinetics

Povidone is not absorbed systemically when applied topically, as it remains localized at the site of application. Its pharmacokinetics are largely dependent on the formulation and route of administration, with the polymer being metabolized by hydrolysis and excreted in urine as low-molecular-weight compounds. The release and activity of iodine are influenced by the concentration of povidone and the presence of organic matter.

Adverse effects

• Local irritation
• Allergic reactions
• Skin rashes
• Hypersensitivity reactions

Precautions

• Use with caution in patients with known allergies to iodine or povidone-iodine
• Avoid use in deep puncture wounds or serious burns

Pregnancy

Povidone is generally considered safe for use during pregnancy, but it is advisable to consult a healthcare professional before use.

Breast-feeding

Povidone is considered safe during breastfeeding, but it is recommended to consult a healthcare professional.

Storage

Store at room temperature, away from moisture and heat. Keep the container tightly closed.

Formulations

• Topical solution
• Ointment
• Surgical scrub
• Gauze impregnated with povidone-iodine