IMERON 400

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

• Intravenous urography
• CT angiography
• Contrast-enhanced computed tomography (CT) scans
• Magnetic resonance angiography (MRA)
• Angiographic studies

Dosage

Children: Refer to the BNF for Children for specific paediatric dosing information based on the procedure and patient condition.

Adults: Refer to the BNF for specific dosing information based on the procedure and patient condition.

Mechanism of action

Iomeprol acts as a radiographic iodinated contrast agent that opacifies the vessels and body structures where it is administered. Following intravenous or intra-arterial administration, it permits radiographic visualization by attenuating X-ray photons. In normal physiological conditions, the contrast agent does not diffuse into the extravascular space due to an intact blood-brain barrier, while in patients with a disrupted barrier, it can accumulate in the extravascular space.

Pharmacodynamics

The degree of radiographic enhancement provided by iomeprol is directly related to the iodine concentration in the targeted tissue after administration. Although it enhances imaging quality, the exposure-response relationships and the complete pharmacodynamic response profile of iomeprol have not been fully detailed. Importantly, at therapeutic concentrations, it does not significantly affect the cardiovascular, central nervous, renal, or complement systems.

Pharmacokinetics

Iomeprol's pharmacokinetic profile includes distribution within the vascular system following administration, with the contrast agent primarily remaining within the vessels in healthy conditions. Its elimination pathways, metabolism, and excretion details are not specified, but it is primarily eliminated via the kidneys, similar to other iodinated contrast agents.

Adverse effects

• Nausea
• Vomiting
• Headache
• Allergic reactions
• Hypotension
• Extravasation at injection site

Precautions

• Use with caution in patients with a history of allergy to iodinated contrast agents
• Monitor renal function in patients with pre-existing renal impairment
• Ensure adequate hydration before and after administration
• Consider the risk of contrast-induced nephropathy in high-risk patients

Pregnancy

Iomeprol should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus, as it is a category C drug.

Breast-feeding

Iomeprol is excreted in breast milk; caution should be exercised when administered to breastfeeding women.

Storage

Store at room temperature, protected from light. Do not freeze.

Formulations

• Iomeprol 300 mg/ml solution for injection
• Iomeprol 400 mg/ml solution for injection

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

Iomeprol is a radiographic iodinated contrast agent that opacifies the vessels and body structures where the contrast agent is present following intravenous or intra-arterial administration, permitting radiographic visualization of the internal structures through attenuation of X-ray photons. In imaging of the body, iodinated contrast agents diffuse from the vessels into the extravascular space. In normal brain with an intact blood-brain barrier, the contrast agent does not diffuse into the extravascular space and contrast enhancement is generally due to the presence of contrast within the vascular space. In patients with a disrupted blood-brain barrier, the contrast agent accumulates in the extravascular space in the region of disruption.

Pharmacodynamics

The degree of radiographic enhancement by iomeprol is related to the iodine concentration in the tissue of interest following the administration of iomeprol. However, the exposure-response relationships and time course of pharmacodynamic response of iomeprol have not been fully characterized. At therapeutic concentrations, iomeprol was not shown to cause significant effects on the cardiovascular, central nervous, renal, and complement systems.