Ultravist

Indications

• Iodine deficiency
• Goiter
• Hypothyroidism
• Thyroiditis
• Fibrocystic breast disease

Dosage

Children: Refer to the BNF for Children for appropriate dosing guidelines based on age and weight.

Adults: Refer to the BNF for appropriate dosing guidelines based on condition and clinical judgment.

Mechanism of action

Molecular iodine inhibits the induction and promotion of carcinogenesis in mammary tissues and has shown beneficial effects in fibrocystic breast disease. It temporarily decreases thyroid hormone production through the acute Wolff-Chaikoff effect, followed by a return to normal hormone synthesis due to down regulation of the sodium-iodide symport. This mechanism can lead to a transient hypothyroid state in some individuals with underlying thyroid conditions.

Pharmacodynamics

Iodine is vital for the synthesis of thyroid hormones thyroxine (T4) and triiodothyronine (T3). It affects the metabolism of amine-derived hormones and plays a role in amino acid metabolism. The acute excess of iodide can lead to decreased circulating levels of T4 and T3 in susceptible individuals, while most people can escape this effect and maintain normal thyroid function.

Pharmacokinetics

Iodine is absorbed primarily in the gastrointestinal tract and is distributed throughout the body, particularly in the thyroid gland, where it is concentrated for hormone synthesis. The kidney plays a significant role in the excretion of excess iodine. The half-life of iodine in the body varies and can be influenced by dietary intake and underlying health conditions.

Adverse effects

• Hypothyroidism
• Hyperthyroidism
• Iodine allergy
• Gastrointestinal disturbances

Interactions

• Thyroid hormones
• Antithyroid drugs
• Lithium
• Diuretics

Precautions

• Use with caution in patients with thyroid dysfunction
• Monitor thyroid function periodically during treatment
• Pregnant or breastfeeding women should consult a healthcare provider before use

Pregnancy

Iodine is essential for fetal thyroid hormone synthesis, but excessive iodine intake should be avoided.

Breast-feeding

Iodine is excreted in breast milk; consult a healthcare provider regarding supplementation.

Storage

Store in a cool, dry place away from light.

Formulations

• Iodine solution
• Iodine tincture
• Potassium iodide tablets

Indications

• Diagnostic imaging of the vascular system
• Contrast-enhanced computed tomography (CT) scans
• Angiography
• Excretory urography

Dosage

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

Adults: The dosing of iopromide depends on the specific imaging procedure and patient characteristics. Refer to the BNF for detailed dosing guidelines.

Mechanism of action

Iopromide works by increasing the contrast of radiographic images through its iodine content, which absorbs X-rays. After intravascular injection, it enhances the visibility of blood vessels and tissues, allowing for clearer imaging during diagnostic procedures.

Pharmacodynamics

Following intravenous injection, opacification of the renal parenchyma begins within 1 minute. The excretion of iopromide is noticeable within 1 to 3 minutes, with optimal contrast observed in the calyces and collecting system occurring between 5 and 15 minutes. In patients with nephropathic conditions, the excretion rate may be unpredictable, with possible delays in opacification for several hours. The effectiveness of the contrast enhancement is directly related to the iodine concentration present in the targeted tissue.

Pharmacokinetics

Iopromide is primarily eliminated through renal excretion. The pharmacokinetics can vary significantly in patients with impaired renal function, which may affect the time taken for the contrast agent to be excreted and the subsequent imaging outcomes. Its distribution and elimination largely depend on the patient's renal capacity.

Contra-indications

• Hypersensitivity to iopromide or any of its components
• Severe renal impairment
• Uncontrolled hyperthyroidism or thyroid storm

Adverse effects

• Nausea
• Vomiting
• Headache
• Dizziness
• Injection site reactions
• Hypotension
• Allergic reactions
• Nephrotoxicity
• Thyroid dysfunction

Interactions

• May enhance the effects of anticoagulants
• Potential interaction with other nephrotoxic agents

Precautions

• Caution in patients with renal impairment
• Caution in patients with a history of allergic reactions to contrast media
• Adequate hydration should be ensured before and after administration
• Monitor renal function post-procedure

Pregnancy

Iopromide should only be used if the potential benefit justifies the potential risk to the fetus. It is recommended to avoid use in pregnancy unless necessary.

Breast-feeding

Iopromide is excreted in breast milk in small amounts. Caution should be exercised when administering to a nursing mother.

Storage

Store at room temperature (15-25 degrees Celsius). Protect from light. Do not freeze.

Formulations

• Iopromide 300 mg I/mL
• Iopromide 370 mg I/mL

Mechanism of action

Molecular iodine is known to inhibit the induction and promotion of N-methyl-n-nitrosourea-induced mammary carcinogenesis, to regress 7,12-dimethylbenz(a)anthracene-induced breast tumors in rats.It has also been shown to have beneficial effects in fibrocystic human breast disease. An acute iodide excess (above the preexisting dietary intake) transiently decreases the production of thyroid hormones in the thyroid gland; this is referred to as the acute Wolff-Chaikoff effect. In normal people, this is followed by a return to normal levels of hormone synthesis, referred to as escape from the acute Wolff-Chaikoff effect, without a significant change in circulating hormone levels. Escape is thought to be the result of down regulation of the sodium-iodide symport (NIS), the iodide transporter in the thyroid gland, resulting in a decrease in the intrathyroidal iodine and the resumption of normal hormone synthesis. An acute or chronic excess of iodide can also decrease circulating T4 and T3 levels and induce a hypothyroid state in some people who have underlying thyroid disorders. These effects are the result of a failure to escape from the acute Wolff-Chaikoff effect. Most people who experience iodine-induced hypothyroidism recover when the excess iodine intake is discontinued.

Mechanism of action

Iopromide is a nonionic iodinated, water-soluble, radiographic contrast medium that is available in two stable, ready-to-use solutions of different concentrations (i.e., 300 mg I/mL and 370 mg I/mL). Following intravascular injection, iopromide provides radiographic opacification of the vasculature and extracellular space in the path of flow of the agent, allowing diagnostic assessment of the limbs and internal organs until significant dilution occurs.

Pharmacodynamics

After intravenous injection, opacification of the renal parenchyma begins within 1 minute. Excretion of the contrast agent becomes apparent in 1 to 3 minutes with optimal contrast in the calyces and collecting system occurring between 5 and 15 minutes. In nephropathic conditions, particularly when excretory capacity has been altered, the excretion rate varies unpredictably and opacification may be delayed for several hours after injection. the degree of contrast enhancement is related to the iodine concentration in the tissue of interest.