Iodomarin® 100

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT JODOMARIN® 100 (JODOMARIN® 100)

Composition:

Active substance: potassium iodide;

One tablet contains 131 μg of potassium iodide, equivalent to 100 μg of iodide;

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

Pharmaceutical form. Tablets.

Main physicochemical properties: tablets with flat parallel surfaces, beveled edges, and a score line on one side for dividing; tablet color at batch release – from white to almost white, and during shelf life – from white to creamy white.

Pharmacotherapeutic group.

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

Pharmacological properties.

Pharmacodynamics.

Iodomarin® 100 is a medicinal product containing inorganic iodine. Iodine is an essential trace element incorporated into thyroid hormones, thyroxine (T4) and triiodothyronine (T3), and ensures normal thyroid gland function.

After iodide enters 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-diiodinated derivative (thyroxine hormone – T4) and the 3-iodinated derivative (triiodothyronine hormone – T3). Thyronines form a complex with the protein thyroglobulin, which is stored in the colloid of the thyroid follicles and remains in this form for several days to weeks. In iodine deficiency, this process is impaired. Iodine supplied in physiological amounts prevents the development of iodine-deficiency goiter; normalizes thyroid gland size in newborns, infants, children, and adult patients; and influences the T3/T4 ratio and thyrotropin (TSH) levels.

Pharmacokinetics.

After oral administration, inorganic iodine is almost completely absorbed in the small intestine.

Within 2 hours after absorption, it distributes into the extracellular space and accumulates in the thyroid gland, kidneys, stomach, mammary glands, and salivary glands. The volume of distribution in healthy individuals averages 23 liters (38% of body weight). Plasma concentration after standard dosing ranges from 10 to 50 ng/mL, while iodine concentrations in breast milk, saliva, and gastric juice are approximately 30 times higher than in plasma. The thyroid gland contains about 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 development, 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 iodine-deficiency goiter in children, including newborns and infants, and in young adults.

Contraindications.

Hypersensitivity to the active substance or to any of the excipients of the medicinal product. Marked hyperthyroidism. In case of latent hyperthyroidism, the medicinal product is contraindicated at doses exceeding 150 mcg 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 mcg 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 types of interactions.

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

Substances taken up by the thyroid gland via the same uptake mechanism as iodine may inhibit iodine uptake by the thyroid gland through a competitive mechanism (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 cause hyperkalemia.

Concomitant use increases the cardiac effect of quinidine due to elevated plasma potassium concentration.

Simultaneous administration with plant alkaloids and heavy metal salts may lead to 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 and in the presence of, or suspicion for, thyroid cancer. It should be taken into account that treatment with this medicinal product in patients with renal insufficiency may lead to the development of hyperkalemia.

The medicinal product Iodomarin® 100 contains lactose. Iodomarin® 100 should not be administered to patients with rare hereditary galactose intolerance, severe lactase deficiency, or glucose-galactose malabsorption syndrome.

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

Use during pregnancy or breastfeeding.

During pregnancy and breastfeeding, the requirement for iodine is increased; therefore, adequate iodine intake (250 μg per day) is particularly important. Due to the ability of iodine to cross the placenta and the fetus's sensitivity to pharmacologically active doses of iodine, it should be used only in the recommended doses. This also applies to the breastfeeding period, as the concentration of iodine in breast milk is 30 times higher than in blood serum.

The exception is high-dose iodine prophylaxis carried out after nuclear or radiological accidents.

Ability to affect reaction rate when driving or operating machinery.

No effect.

Method of Administration and Dosage

Prevention of iodine deficiency and endemic goiter when the daily intake of iodine in adults is less than 150–200 mcg: an additional amount should be administered as follows:

Newborns, infants, and children up to 12 years of age: 50–100 mcg of iodine per day (½ to 1 tablet of the medicinal product Iodomarin® 100).

Children aged 12 years and older, and adults: 100–200 mcg of iodine per day (1 to 2 tablets of the medicinal product Iodomarin® 100).

Pregnancy or breastfeeding period: 200 mcg of iodine per day (2 tablets of the medicinal product Iodomarin® 100).

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

Children and adults: 100–200 mcg of iodine per day (1 to 2 tablets of the medicinal product Iodomarin® 100).

Treatment of diffuse euthyroid iodine-deficiency goiter.

Newborns, infants, and children: 100–200 mcg of iodine per day (1 to 2 tablets of the medicinal product Iodomarin® 100).

Young adults: 300–500 mcg of iodine per day (3 to 5 tablets of the medicinal product Iodomarin® 100).

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 a crushed form. Prophylactic use of the medicinal product is generally carried out for several months or years, and more often for life. For treatment of goiter in newborns and infants, 2–4 weeks are usually sufficient in most cases; in children and adults – 6–12 months or longer. In general, the physician determines individually the dosage and duration of administration of the medicinal product 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. 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. Development of edema, erythema, acneiform and bullous rashes, hemorrhages, fever, and nervous excitement is possible.

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 disturbances in water and electrolyte balance; if necessary, anti-shock therapy should be performed.

Therapy for chronic intoxication: withdrawal of 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 depends on clinical course: mild forms usually do not require treatment; pronounced forms require antithyroid therapy (which has delayed effectiveness). In the most severe cases (thyrotoxic crisis), intensive therapy, plasmapheresis, or thyroidectomy are necessary.

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 foci in the thyroid gland and when iodine is administered in daily doses exceeding 150 mcg, the occurrence of pronounced hyperthyroidism cannot be completely excluded.

The following side effects 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); not known (cannot be estimated based on available data).

Immune system disorders.

Very rare: hypersensitivity reactions (e.g. 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 diffuse euthyroid iodine-deficiency goiter in adults, iodine-induced hyperthyroidism may occur in individual cases. The main predisposing factor for this is the presence of diffuse or localized autonomous areas in 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 mucosal swelling of the nose, urticaria, Quincke's edema, skin rashes, itching, and in isolated cases— anaphylactic shock), eosinophilia, tachycardia, tremor, irritability, sleep disturbances, increased sweating, epigastric discomfort, diarrhea. When the drug is used in high doses, goiter and hypothyroidism may develop in individual cases.

Reporting suspected side effects.

Reporting of suspected adverse reactions after drug registration is of great importance. It allows continuous monitoring of the benefit-risk balance of the medicinal product. Medical and pharmaceutical professionals, as well as patients or their legal representatives, should report all cases of suspected adverse reactions and lack of drug efficacy via the Automated Information System for Pharmacovigilance 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 30 °C. Keep out of reach of children.

Packaging.

Brown glass bottle containing 50 or 100 tablets; 1 bottle in a cardboard box.

Prescription status.

Over-the-counter.

Manufacturer.

BERLIN-CHEMIE AG.

Manufacturer's address and location of business activity.

Glienicker Weg 125, 12489 Berlin, Germany.