Natriumiodid (I131) Zur Therapie Curium Netherlands (Sodium Iodide (131i))

Natriumiodid (I‑131) is used in radioiodine therapy targeting thyroid tissue.

• Thyroid cancer: facilitates selective destruction of residual thyroid tissue after surgery, reducing recurrence risk.
• Hyperthyroidism: ablates overactive thyroid cells to control excess hormone production.
• Thyroid ablation: prepares patients for radioactive iodine uptake scans or subsequent therapeutic dosing by eliminating remaining functional thyroid tissue.

• After oral administration, sodium iodide (I‑131) is absorbed and preferentially taken up by thyroid follicular cells via the sodium‑iodide symporter. The iodine isotope emits beta particles that deliver localized radiation, causing DNA damage and cell death within the thyroid tissue while sparing most surrounding structures. This targeted radiotoxic effect reduces hormone synthesis and eliminates malignant or hyperfunctioning cells.

Natriumiodid (I‑131) may be associated with a range of adverse reactions, varying in frequency and severity.

Common Side Effects

• Nausea: mild to moderate upset stomach after dosing.
• Vomiting: occasional emesis within hours of administration.
• Dry mouth: reduced salivation reported by some patients.
• Taste alteration: temporary metallic or bitter taste sensation.
• Neck discomfort: mild soreness in the thyroid region.
• Transient hypothyroidism: temporary reduction in thyroid hormone levels.

Serious or Rare Side Effects

• Severe radiation thyroiditis: painful inflammation of the thyroid gland.
• Bone marrow suppression: decreased blood cell production leading to anemia or infection risk.
• Secondary malignancies: rare risk of new cancers due to radiation exposure.
• Allergic reactions: rash, itching, or anaphylaxis in hypersensitive individuals.
• Pulmonary fibrosis: rare scarring of lung tissue.
• Severe gastrointestinal bleeding: uncommon but serious bleeding events.

Before using Natriumiodid (I‑131), consider the following safety measures.

• Pregnancy: avoid use unless benefits outweigh risks, as fetal thyroid may be affected.
• Breastfeeding: discontinue nursing; consider alternative feeding methods.
• Renal impairment: assess renal function before dosing.
• Concurrent thyroid hormone therapy: monitor hormone levels closely.
• Radiation safety: follow local regulations to protect staff and family.
• Store at ambient temperature: keep in original container, protect from light and moisture.

Natriumiodid (I‑131) can interact with several medications; awareness helps manage potential effects.

Major Interactions (Avoid)

• Thyroid hormone replacement (levothyroxine): may reduce efficacy; dose adjustment may be needed.
• Antithyroid drugs (methimazole, propylthiouracil): can block iodine uptake, diminishing treatment effect.
• Lithium: interferes with iodine organification, reducing therapeutic outcome.

Moderate Interactions (Monitor Closely)

• Amiodarone: high iodine content may affect uptake; monitor thyroid function.
• Corticosteroids: may alter inflammatory response; observe for side effects.
• Diuretics: affect renal clearance of iodine; monitor renal function.