Iodomarin® 200

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT JODOMARIN® 200 (JODOMARIN® 200)

Composition:

Active substance: potassium iodide;

One tablet contains potassium iodide 262 mcg, equivalent to 200 mcg of iodide;

Excipients: lactose monohydrate, light magnesium carbonate, gelatin, sodium starch glycolate (type A), colloidal silicon dioxide anhydrous, magnesium stearate.

Pharmaceutical form. Tablets.

Main physicochemical properties: flat-faced tablets, white or almost white, with bevelled edges and a score line on one side for division.

Pharmacotherapeutic group.

Medicinal products for treatment of thyroid disorders. Thyroid agents. Iodine-containing medicinal products. ATC code H03CA.

Pharmacological Properties

Pharmacodynamics

Iodomarin® 200 is an inorganic iodine medicinal product. Iodine is an essential trace element that is part of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3), thus ensuring normal thyroid function.

After iodides enter the epithelial cells of thyroid follicles, under the influence of the enzyme iodide-peroxidase, oxidation of iodine occurs, resulting in the formation of elemental iodine. This substance undergoes a substitution reaction with the aromatic ring of tyrosine, leading to the formation of thyronines: the 3,5-iodinated derivative (thyroxine hormone – T4) and the 3-iodinated derivative (triiodothyronine hormone – T3). The thyronines form a complex with the protein thyroglobulin, which is stored in the colloid of the thyroid follicle and remains in this state for several days and weeks. In iodine deficiency, this process is impaired. Iodine supplied in physiological amounts prevents the development of endemic goiter associated with dietary deficiency of this element; normalizes thyroid gland size in newborns, infants, children, and young adult patients; and influences T3/T4 ratio parameters and levels of thyroid-stimulating hormone (TSH).

Pharmacokinetics

After oral administration, iodine is almost completely absorbed in the small intestine. Within 2 hours after absorption, it is distributed into the extracellular space and accumulates in the thyroid gland, kidneys, stomach, and in the mammary and salivary glands. The volume of distribution in healthy individuals averages 23 liters (38% of body weight). Plasma concentration after administration of a standard dose ranges from 10 to 50 ng/mL, while iodine levels in breast milk, saliva, and gastric juice are 30 times higher than plasma concentrations. The thyroid gland contains approximately three-quarters (10–20 mg) of the total body iodine. Iodine is primarily excreted in urine, to a lesser extent in feces and exhaled air. At equilibrium, the amount of iodine excreted is proportional to the daily dietary intake of iodine.

Clinical characteristics.

Indications.

Prevention of iodine deficiency, including during pregnancy or breastfeeding.

Prevention of recurrence of iodine-deficiency goiter after surgical treatment, as well as after completion of combined therapy with thyroid hormone medications.

Treatment of diffuse euthyroid goiter in children, including newborns and infants, and young adults.

Contraindications.

History of hypersensitivity to the active substance or to any of the excipients of the medicinal product. Marked hyperthyroidism. In cases of latent hyperthyroidism, the medicinal product is contraindicated at doses exceeding 150 \µg iodine per day. In cases of autonomous adenoma, as well as focal and diffuse autonomous foci of the thyroid gland, the medicinal product is contraindicated at doses of 300 to 1000 \µg iodine per day (except for preoperative iodine therapy for thyroid blockade according to Plummer). Pulmonary tuberculosis. Hemorrhagic diathesis. Dermatitis herpetiformis Duhring (Duhring-Brocq syndrome).

Interaction with other medicinal products and other forms of interaction.

Iodine deficiency enhances the response to antithyroid therapy, whereas iodine excess reduces it; therefore, iodine intake should be avoided, if possible, prior to or during treatment of hyperthyroidism. Antithyroid medicinal products, on their part, inhibit the incorporation of iodine into organic compounds in the thyroid gland and thus may induce goiter formation.

Substances that are taken up by the thyroid gland via the same uptake mechanism as iodine may competitively inhibit iodine uptake by the thyroid gland (e.g. perchlorate, which additionally inhibits iodide recycling within the thyroid gland). Inhibition may also occur with medicinal products that are not themselves taken up, such as thiocyanate at concentrations exceeding 5 mg/dL.

Iodine uptake by the thyroid gland and iodine metabolism within the gland are stimulated by endogenous and exogenous thyroid-stimulating hormone (TSH).

Concomitant treatment with high doses of iodine, which suppress thyroid hormone secretion, and lithium salts may promote the development of goiter and hypothyroidism.

High doses of potassium iodide in combination with potassium-sparing diuretics may lead to hyperkalemia.

When used concomitantly, the cardiac effects of quinidine are enhanced due to increased plasma potassium concentration.

Concomitant use with plant alkaloids and heavy metal salts may result in the formation of an insoluble precipitate and impaired iodine absorption.

Special precautions for use.

This medicinal product should not be used in hypothyroidism, except in cases where hypothyroidism is caused by iodine deficiency. Administration of iodine should be avoided during radioactive iodine therapy, or in the presence of, or suspicion of, thyroid cancer. It should be noted that treatment with this medicinal product in patients with renal insufficiency may lead to the development of hyperkalemia.

Iodomarin® 200 contains lactose. Iodomarin® 200 should not be taken by patients with rare hereditary galactose intolerance, severe lactase deficiency, or glucose-galactose malabsorption syndrome.

This medicinal product contains less than 1 mmol (23 mg) of sodium per tablet, i.e. it is practically "sodium-free".

Use during pregnancy or breastfeeding.

During pregnancy and breastfeeding, iodine requirements are increased; therefore, adequate iodine intake (200 μg per day) is particularly important. Due to iodine's ability to cross the placenta and the fetus's sensitivity to pharmacologically active doses of iodine, iodine should be used only at recommended doses. This also applies to the breastfeeding period, as iodine concentration in breast milk is 30 times higher than in blood serum. The exception is high-dose iodine prophylaxis administered after nuclear accidents.

Ability to affect reaction rate when driving vehicles or operating machinery.

No influence.

Method of Administration and Dosage.

Prevention of iodine deficiency and endemic goiter when daily iodine intake is less than 150–200 mcg:

Newborns, infants, and children under 12 years of age: 50–100 mcg iodine per day (100 mcg iodine is equivalent to ½ tablet of Iodomarin® 200. To achieve a 50 mcg dose, medicinal products with appropriate active ingredient content should be used).

Children aged 12 years and older, and adults: 100–200 mcg iodine per day (½ to 1 tablet of Iodomarin® 200).

Pregnancy or lactation period: 200 mcg iodine per day (1 tablet of Iodomarin® 200).

Prevention of recurrence of iodine-deficiency goiter after surgical treatment, or after completion of combined therapy with thyroid hormones.

Children and adults: 100–200 mcg iodine per day (½ to 1 tablet of Iodomarin® 200).

Treatment of euthyroid goiter.

Newborns, infants, and children: 100–200 mcg iodine per day (½ to 1 tablet of Iodomarin® 200).

Young adults: 300–500 mcg iodine per day (1½ to 2½ tablets of Iodomarin® 200).

Method of Administration.

Tablets should be taken after meals with sufficient liquid, for example, a glass of water. For infants and children under 3 years of age, the medicinal product may be administered in crushed form. Prophylactic use of the medicinal product is generally carried out for several months or years, and more often, throughout life. For treatment of goiter in newborns and infants, 2–4 weeks is usually sufficient; in children and adults, treatment lasts 6–12 months or longer. In general, the physician determines individually the dosage and duration of administration for prophylactic purposes or for treatment of thyroid disorders.

Children.

The medicinal product may be used in children of any age when indicated.

Overdose.

Symptoms of intoxication: brown discoloration of mucous membranes, reflex vomiting (blue discoloration if starch is present in food), abdominal pain, diarrhea (possibly with blood in stools), dehydration, and shock. In isolated cases, esophageal strictures have been observed. Fatal cases have been reported only after ingestion of large amounts of iodine (30–250 ml of tincture of iodine). In individual cases, chronic overdose may lead to so-called iodism, i.e., iodine intoxication: metallic taste in the mouth, swelling and inflammation of mucous membranes (rhinitis, conjunctivitis, gastroenteritis, bronchitis). Iodide may activate latent inflammatory processes such as tuberculosis. Possible development of edema, erythema, acneiform and bullous rashes, hemorrhages, fever, and nervous excitement.

Treatment.

Therapy for acute intoxication: gastric lavage with starch solution, egg white, or 5% sodium thiosulfate solution until all traces of iodine are removed. Symptomatic therapy should be administered to correct water and electrolyte imbalances; if necessary, anti-shock therapy should be initiated.

Therapy for chronic intoxication: discontinue iodine.

Hypothyroidism caused by iodine intake: discontinue iodine; prescribe thyroid hormones to normalize metabolism.

Hyperthyroidism caused by iodine intake: this is not overdose in the literal sense, as hyperthyroidism may also occur with iodine amounts considered physiological in other countries.

Treatment according to clinical course: mild forms usually do not require treatment; pronounced forms require antithyroid therapy (whose effectiveness is delayed in time). In the most severe cases (thyrotoxic crisis), intensive therapy, plasmapheresis, or thyroidectomy are required.

Side effects.

When iodide is used prophylactically in patients of any age, as well as therapeutically in newborns, infants, and children, adverse effects are generally not observed. However, in the presence of large autonomous areas of the thyroid gland and when iodine is administered in daily doses exceeding 150 mcg, the occurrence of pronounced hyperthyroidism cannot be completely ruled out.

The side effects listed below occurred with the following frequencies: very common (≥1/10); common (≥1/100 to <1/10); uncommon (≥1/1000 to <1/100); rare (≥1/10,000 to <1/1000); very rare (<1/10,000); unknown (cannot be estimated based on available data).

Immune system disorders.

Very rare: hypersensitivity reactions (such as iodine-induced rhinitis, bullous or tuberous iododerma, exfoliative dermatitis, angioneurotic edema, fever, acne, and salivary gland swelling).

Endocrine system disorders.

Very rare: during treatment of goiter in adults (daily dose of 300 to 1000 mcg iodine), iodine-induced hyperthyroidism may develop. In the majority of cases, this is predisposed by the presence of diffuse or localized autonomous areas of the thyroid gland. This primarily affects elderly patients who have suffered from goiter for a long time.

Also possible: symptoms of iodism (including such symptoms as nasal mucosa edema, urticaria, Quincke's edema, skin rashes, pruritus, and in isolated cases— anaphylactic shock), eosinophilia, tachycardia, tremor, irritability, sleep disturbances, increased sweating, epigastric discomfort, diarrhea. When the medicinal product is used in high doses, in individual cases, goiter and hypothyroidism may develop.

Reporting of suspected adverse reactions.

Reporting suspected adverse reactions after the medicinal product has been authorized is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals and pharmacists, as well as patients or their legal representatives, are encouraged to report all suspected adverse reactions and lack of efficacy via the Automated Pharmacovigilance Information System at the following link:

https://aisf.dec.gov.ua.

Shelf life.

3 years.

Do not use the medicinal product after the expiry date stated on the packaging.

Storage conditions.

Store at a temperature not exceeding 25 °C.

Keep out of reach and sight of children.

Packaging.

Carton box containing 2 blisters of 25 tablets each.

Availability.

Over-the-counter.

Manufacturer.

BERLIN-CHEMIE AG.

Manufacturer's address and location of business activity.

Glienicker Weg 125, 12489 Berlin, Germany.