Iodine


Concise Prescribing Info
Indications/Uses
Listed in Dosage.
Dosage/Direction for Use
Adult : PO Preoperative reduction of vascularity of the thyroid gland In conjunction with antithyroid agents: As 5% w/v iodine with 10% w/v K iodide solution: 0.1-0.3 mL tid for 6 days. Radiation protection against radioactive iodine As K iodate tab: 170 mg as single daily dose. Topical Antiseptic; Minor, superficial skin wounds As 2% or 2.5% solution: Apply small amount to the affected area 1-3 times daily. Cleaning wet ulcers and wounds As 0.9% cadexomer-iodine ointment, paste or powder: Max: 50 g as a single application on clean wound; 150 g/week. May change dressing for approx 3 times weekly, then reduce applications as exudates decrease for up to ≤3 months. Discontinue if wound is free of exudate.
Dosage Details
Oral
Preoperative reduction of vascularity of the thyroid gland
Adult: In conjunction with antithyroid agents: As 5% w/v iodine with 10% w/v K iodide solution: 0.1-0.3 mL in milk or water tid for 6 days.

Oral
Radiation protection against radioactive iodine
Adult: As K iodate tab: 170 mg as single daily dose given within 3 hours (or up to 10 hours) of nuclear accident. Radiation protection persists for up to 24 hours.
Child: As K iodate tab: <1 month 21.25 mg; 1 month to 3 years 42.5 mg; 3-12 years 85 mg; >12 years Same as adult dose. All doses are given as single daily dose, may be crushed and mixed with milk or water.

Topical/Cutaneous
Cleaning wet ulcers and wounds
Adult: As 0.9% cadexomer-iodine ointment, paste or powder: Apply to clean wounds as directed. Max: 50 g as a single application on clean wound; 150 g weekly. Change dressing for approx 3 times weekly, then reduce applications as exudates decrease. Discontinue if wound is free of exudate. Max duration: 3 months.

Topical/Cutaneous
Antiseptic, Minor, superficial skin wounds
Adult: As 2% iodine tincture or 2.5% iodine with K iodide: Apply small amount to the affected area 1-3 times daily.
Child: Same as adult dose.
Incompatibility
Forms a pungent irritating compound with acetone.
Contraindications
Hypersensitivity. Hypocomplementaemic vasculitis, dermatitis herpetiformis, nodular thyroid conditions with cardiac disease. Topical: Neonates, pregnancy and lactation; concomitant lithium therapy. Renal failure (K iodate tab).
Special Precautions
Patient with current or history of thyrotoxicosis, nodular goitre or latent Graves’ disease, adrenal insufficiency (e.g. Addison’s disease), acute bronchitis, tuberculosis, myotonia congenita, cardiac disease, acute dehydration, heat cramp. Not recommended for long term treatment. Avoid applying to large areas of the body or covering affected area with occlusive dressings (topical). Renal impairment. Children, especially neonates. Pregnancy and lactation.
Adverse Reactions
Significant: Thyroid-related reactions (e.g. iodine-induced hypo- or hyper-thyroidism, thyroiditis, thyroid enlargement); iodism or chronic iodine poisoning (prolonged treatment); hypersensitivity reactions (e.g. urticaria, angioedema, cutaneous haemorrhage or purpura); acne flare-ups, dermatitis.
Blood and lymphatic system disorders: Lymphadenopathy, eosinophilia.
Cardiac disorders: Cardiac arrhythmia.
Eye disorders: Lacrimation, conjunctivitis.
Gastrointestinal disorders: Nausea, vomiting, diarrhoea, increased salivation, salivary gland swelling or tenderness, stomach pain.
General disorders and admin site conditions: Fever, oedema, pain or burning sensation, fatigue, influenza-like illness.
Musculoskeletal and connective tissue disorders: Arthralgia.
Nervous system disorders: Headache, metallic taste, numbness, tingling sensation.
Psychiatric disorders: Insomnia, depression, confusion, nervousness.
Reproductive system and breast disorders: Impotence, erectile dysfunction.
Respiratory, thoracic and mediastinal disorders: Laryngitis, bronchitis, coryza-like symptoms.
Skin and subcutaneous tissue disorders: Rash, iodine burns, myxoedema.
MonitoringParameters
Monitor thyroid function tests especially in pregnant women, children and neonates. Assess for signs and symptoms of hyperthyroidism.
Overdosage
Symptoms: Metallic taste, thirst, vomiting, headache, abdominal pain, diarrhoea; swelling of epiglottis causing asphyxia, aspiration, pneumonia or pulmonary oedema may lead to death. Systemic toxicity may result to fever, shock, tachycardia, metabolic acidosis and renal failure. Management: Symptomatic and supportive treatment. May administer copious amounts of milk and starch mucilage. If there is no evidence of oesophageal damage, may consider stomach aspiration or gastric lavage with dilute starch mucilage or 1% Na thiosulfate solution; activated charcoal within 1 hour of ingestion. Maintain circulation and replace electrolyte or water losses. May consider giving pethidine or morphine sulfate for pain only under medical supervision. May perform tracheotomy if necessary.
Drug Interactions
May cause additive hypothyroid and goitrogenic effects of lithium carbonate, iodides and amiodarone. May increase risk of hyperkalaemia with K-sparing diuretics (e.g. amiloride, triamterene), angiotensin II receptor antagonist, ACE inhibitors (e.g. captopril, enalapril); aliskiren, nicorandil, heparin. May enhance cardiac effect of quinidine.
Lab Interference
May interfere with thyroid function tests.
Action
Description: Iodine, a non-metallic element, temporarily blocks the thyroid hormone synthesis and secretion into circulation and reduces the thyroid gland size and vascularity. Iodine (as K iodide or K iodate) also inhibits the uptake of radioiodine by the thyroid gland thereby reducing the risk of thyroid cancer following radioactive iodine exposure. Topical iodine also acts as a powerful broad-spectrum germicidal agent by disrupting and penetrating the cell walls of microorganisms.
Onset: Hyperthyroidism: 24-48 hours.
Pharmacokinetics:
Absorption: Rapidly absorbed from the gastrointestinal tract and transported into the thyroid gland; Slightly absorbed in the skin.
Distribution: Concentrated in the thyroid gland. Crosses the placenta and enters in breast milk.
Metabolism: Metabolised by amylases present in the wound fluid (topical). Converted to iodide.
Excretion: Mainly via urine (>90%); faeces, sweat and saliva (small amounts).
Storage
Store below 25°C. Keep in tight, light-resistant containers.
ATC Classification
D08AG03 - iodine ; Belongs to the class of iodine product antiseptics. Used in the treatment of dermatological diseases.
Disclaimer: This information is independently developed by MIMS based on Iodine from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2020 MIMS. All rights reserved. Powered by MIMS.com
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