Thyroid Hormones And Anti Thyroid Drugs Question And Answers

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Thyroid Hormones And Anti Thyroid Drugs Important Notes

1. Thyroid Hormones And Anti Thyroid Drugs Thyroid storm

  • It means thyrotoxicosis
  • Treatment is to reduce the production and conversion of thyroid hormones
  • Drugs used for it are
    • Inhibiting thyroid hormone synthesis.
      • Propylthiouracil
      • Methimazole
      • Carbimazole
    • Inhibiting hormone release
      • Iodine
      • Iodide
    • Destroying thyroid tissue
      • Radioactive iodine
    • To counteract adrenal insufficiency
      • Corticosteroids
    • To control sympathetic symptoms
      • Propanolol

Read And Learn More: Pharmacology Question and Answers

2. Thyroid Hormones And Anti-thyroid drugs

  • Propylthiouracil, carbimazole, and radioactive iodine are anti-thyroid drugs
  • Used in the treatment of
    • Hyperthyroidism
    • Preparation of patients for thyroid surgery

Thyroid hormones: question and answer

Thyroid Hormones And Anti-Thyroid Drugs Long Essays

Question 1. Enumerate antithyroid drugs. Explain the action of the thioamides giving the indications, advantages, and adverse effects of each.
Answer:

Antithyroid drugs:

  • These drugs inhibit hormone synthesis.
  • They are thioureylenes or thionamides which includes.
    • Propylthiouracil.
    • Methimazole.
    • Carbimazole.

Antithyroid drugs Actions:

Thyroid Hormones And Anti-Thyrid Drug Action

Antithyroid drugs Indications/uses:

1. Graves disease or diffuse toxic goiter.

  • Needs long-term treatment with antithyroid drugs.

2. Toxic nodular goiter.

  • Used when surgery is not indicated like in elderly patients.

3. Preoperatively in hyperthyroid patients.

  • Used along with radioactive iodine to hasten recovery in thyrotoxicosis.

4. Rarely used in hyperthyroidism in pregnancy.

5. Thyroid storm or thyrotoxic crisis.

  • It is a sudden, severe, exacerbation of thyrotoxicosis.
  • Propylthiouracil is used IV.

Antithyroid drugs Advantages:

  • No surgery is required.
  • No injury to parathyroid or recurrent laryngeal nerve.
  • Hypothyroidism, if occurs, is reversible.
  • Can be used in children and young adults also.

Antithyroid drugs Disadvantages:

  • Long-term treatment is required.
  • Poor patient compliance.
  • Drug toxicity.

Antithyroid drugs Adverse effects:

  • Allergic reactions – skin rashes.
  • Jaundice
  • Headache.
  • Hypothyroidism.
  • Agranulocytosis.
  • GIT disturbances.
  • Joint pain.
  • Nephritis, hepatitis
  • Loss of hair, loss of taste.

Mechanism of thyroid hormone action

Thyroid Hormones And Anti Thyroid Drugs Short Essays

Question 1. Radioactive iodine.
Answer:

Radioactive iodine is a thyroid tissue-destroying agent

  • When given orally, it is rapidly absorbed and is concentrated by the thyroid in the follicles.
  • It emits X-rays as well as β particles.
  • It is used as a sodium salt of 31I dissolved in water.

Radioactive iodine Uses:

1. Small doses – 25 -100 m curie.

  • Used for diagnosis in thyroid function tests.

2. Large doses – 3 – 6 cm curie.

  • Used for treatment of hyperthyroidism.
  • β particles emitted destroy thyroid cells.
  • Thus, it is used in carcinoma of the thyroid.

Radioactive iodine Advantages:

  • Simple and convenient
  • Inexpensive.
  • No surgical risks.
  • Hyperthyroidism is permanently cured.

Radioactive iodine Disadvantages:

  • Slow-acting.
  • The long latent period of response.
  • Hypothyroidism develops.
  • Not suitable for pregnant women, children, and young adults.

Thyroid Hormones And Anti Thyroid Drugs Short Question And Answers

Question 1. Lugol’s iodine.
Answer:

Lugol’s iodine is a solution of 5% iodine in 10% potassium iodide solution.

  • A daily dose of 5 -15 drops can be used.

Lugol’s iodine Uses:

  • As expectorant
  • In preoperative preparation for thyroidectomy.
  • Thyroid storm.
  • Prophylactic in endemic goiter.
  • As antiseptic.

Anti-thyroid drugs classification

Question 2. Iodine.
Answer:

Iodine inhibits the release of thyroid hormone

  • In thyrotoxic patients, symptoms subside in 1 – 2 days.
  • The gland becomes firm and shrinks in size in 10 -14 days.
  • Effects decrease after 15 days.

Iodine Uses:

  • Preoperatively in thyroidectomy.
  • In thyroid storm.
  • Prophylactically in endemic goiter.
  • As antiseptic
  • As expectorant.

Iodine Adverse effects:

  • Allergic reactions – skin rashes, conjunctivitis.
  • Swelling of lips and salivary glands.
  • Fever
  • Lymphadenopathy.

Thyroid drugs pharmacology

Question 3. Carbimazole.
Answer:

Carbimazole is a thioamide.

  • Act as thyroid hormone synthesis inhibitor.
  • It is more potent and long-acting.
  • It crosses the placental barrier.

Carbimazole Uses:

  • long-term therapy of thyrotoxicosis.
  • To hasten recovery in thyrotoxicosis.
  • Used in thyrotoxic crisis.

Carbimazole Adverse effects:

  • Allergic reactions
  • Hypothyroidism.
  • GI intolerance
  • Hepatitis, nephritis.
  • Joints pain.
  • Agranulocytosis.

Question 4. Alendronate.
Answer:

  • It is second generation bisphosphonate
  • Mainly used in osteoporosis
  • Advice to be given on an empty stomach in the morning with plenty of water
  • Avoid lying or having food for at least 30 minutes to avoid oesophagitis
  • Calcium and iron preparation and NSAIDs should not give along with it

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