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Paper II — 2025 March (Supplementary (SAY)) (2019 Scheme) — Q12

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Paper II
2025 March (Supplementary (SAY)) (2019 Scheme) · 100 marks · 180 min

Question

Mechanism of action, uses and adverse effects of Radio active iodine.

Q124 marksShort Answers

Answer

Radioactive iodine (I-131) is used for definitive treatment of hyperthyroidism.

Mechanism: taken up by the thyroid via the sodium-iodide symporter (the same physiological uptake mechanism as normal iodide), concentrating specifically in thyroid tissue; beta-particle emission causes localized cellular damage/destruction over weeks, gradually reducing functional thyroid tissue.

Uses: definitive treatment of Graves’ disease and toxic nodular goitre, differentiated thyroid carcinoma (post-thyroidectomy ablation of residual tissue).

Adverse effects: hypothyroidism (the eventual, expected outcome of adequate treatment, requiring lifelong levothyroxine replacement), transient radiation thyroiditis. Absolutely contraindicated in pregnancy — crosses the placenta and concentrates in the fetal thyroid once it becomes iodine-avid in the second trimester, causing fetal hypothyroidism/cretinism.

  1. 1Thyroid Hormones and Antithyroid Drugs

Other Years Asked

  1. 1T4 and very low TSH levels. A diagnosis of hyperthyroidism was made. (2022 July (Supplementary) (2019 Scheme)Essay · 10 marks
  2. 2Compare Radioactive Iodine and Carbimazole.2024 March (Supplementary) (2019 Scheme)Short Essay · 8 marks
  3. 3Classify Thyroid inhibitor drugs. Describe the mechanism of action, and adverse effects of carbimazole. Explain the role of iodides in hyperthyroidism. (2+2+2)2022 May (Supplementary) (2010 Scheme)Essay · 6 marks
  4. 4(2023 July (Supplementary) (2019 Scheme)Essay · 6 marks
  5. 5A 32years old woman, presented with complaints of weight loss, palpitations, sweating, irregular menses and occasional tremors of hands since 2-3 months. Clinical examination revealed a diffusely enlarged thyroid gland and blood tests showed decreased TSH. She was started on medication for Grave’s disease.2025 March (Supplementary) (2010 Scheme)Essay · 6 marks
  6. 6Classify antithyroid drugs. Write the advantages and disadvantages of using radioactive Iodine. (2+2+2)2021 February (Supplementary) (2010 Scheme)Essay · 6 marks
  7. 7A 35 years old woman came with complaints of heat intolerance, retraction of upper eyelid and menstrual irregularities. Her T3 , T4 , FT4 & FT3 are elevated while TSH is suppressed. Answer the following:2015 February (2010 Scheme)Essay · 6 marks
  8. 8Treatment of thyrotoxic crisis.2023 January (Supplementary) (2019 Scheme)Short Answer · 4 marks
  9. 9Pharmacotherapy of Thyrotoxic crisis (thyroid storm)2024 June (Supplementary) (2019 Scheme)Short Answer · 4 marks
  10. 10Carbimazole2022 October (Supplementary) (2010 Scheme)Short Note · 3 marks
  11. 11Radioactive Iodine2024 March (Supplementary) (2010 Scheme)Short Note · 3 marks
  12. 12Anti thyroid drugs2014 September (Supplementary) (2010 Scheme)Short Note · 3 marks
  13. 13Radioactive Iodine2021 May (Supplementary) (2010 Scheme)Short Note · 3 marks
  14. 14Lugol’s Iodine is given for 10 days prior to thyroidectomy surgery for Grave’s disease.2023 July (Supplementary) (2010 Scheme)Short Answer · 1 mark
  15. 15Anti-thyroid drugs2018 July (Supplementary) (2010 Scheme)Short Answer · 1 mark
  16. 16Explain the use of propranolol in thyrotoxicosis.2018 February (2010 Scheme)Short Answer · 1 mark
  17. 17Methimazole acts by:2024 December (Supplementary) (2019 Scheme)MCQ · 1 mark
  18. 18Antithyroid drugs2013 April (2010 Scheme)Short Answer · 1 mark
  19. 19Drug used in thyrotoxic crisis2014 March (2010 Scheme)Short Answer · 1 mark
  20. 20Propylthiouracil2025 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
  21. 21Anti- thyroid drugs safe during pregnancy2017 August (Supplementary) (2010 Scheme)Short Answer · 1 mark
  22. 22Thyrotoxic crisis.2015 September (Supplementary) (2010 Scheme)Short Answer · 1 mark
  23. 23Anti thyroid drugs2016 October (Supplementary) (2010 Scheme)Short Answer · 1 mark
  24. 24Radioactive iodine2020 February (Supplementary) (2010 Scheme)Short Answer · 1 mark
  25. 25Use of Propranolol in Thyrotoxic crisis.2024 March (Supplementary) (2010 Scheme)Short Answer · 1 mark
  26. 26The preferred drug for her is:2024 December (Supplementary) (2019 Scheme)MCQ · 1 mark
  27. 27 Carbimazole for treatment of Thyroid storm2024 August (Supplementary) (2010 Scheme)Short Answer · 0.3 marks
  28. 28Antithyroid drugs2019 February (2010 Scheme)Short Answer · 0.3 marks

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