Octreotide is a long acting synthetic analogue of:

Correct Answer: C

Rationale: Octreotide is a long-acting synthetic analogue of somatostatin. Somatostatin is a naturally occurring hormone that inhibits the secretion of several other hormones, including growth hormone, insulin, glucagon, and others. Octreotide is often used in the management of conditions like acromegaly (excess growth hormone production), carcinoid syndrome, and some forms of diarrhea associated with hormonal imbalances. By mimicking the actions of somatostatin, octreotide helps to regulate hormone levels in the body and manage symptoms related to hormone excess.

Correct Answer: C

Rationale: Menotropins is a preparation of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) obtained from the urine of menopausal women. Menopausal women have a higher concentration of FSH and LH in their urine compared to menstruating or pregnant women. This preparation is commonly used to induce ovulation in women undergoing fertility treatments. The combination of FSH and LH in menotropins helps stimulate the development of ovarian follicles and triggers ovulation.

Correct Answer: A

Rationale: The metabolic rate of the brain is not significantly affected by thyroxine. Thyroxine mainly influences the metabolic rate of organs with high energy demands such as the heart, liver, and skeletal muscle. Thyroxine increases the metabolic rate by stimulating the production of enzymes involved in energy production and consumption. However, the brain has a relatively stable metabolic rate that is not significantly influenced by changes in thyroid hormone levels.

Correct Answer: D

Rationale: Triiodothyronine (T3) is preferred over thyroxine (T4) in the treatment of Myxoedema coma, which is a severe form of hypothyroidism that can lead to decreased mental function, hypothermia, and even coma. T3 has a faster onset of action and is more potent than T4, making it the preferred choice in emergency situations like myxoedema coma where rapid correction of thyroid hormone levels is crucial to prevent serious complications. In contrast, in conditions like endemic goiter, cretinism, and papillary carcinoma of thyroid, where long-term maintenance therapy is needed, thyroxine (T4) is usually the preferred choice because of its longer half-life and stability of serum levels over time.

Correct Answer: D

Rationale: In this scenario, the correct answer is D) All of the above. The rationale behind this is that overtreatment with any of the thyroid inhibitors listed (Lugol's iodine, Radioactive iodine, and Carbimazole) can lead to enlargement of the thyroid, a condition known as goiter. Lugol's iodine is a solution containing molecular iodine and potassium iodide, which can cause goiter if used in excess. Radioactive iodine, often used in the treatment of hyperthyroidism, can also lead to goiter if the dosage is too high. Carbimazole, a medication used to treat hyperthyroidism, can cause goiter as a side effect when overused or not properly monitored. To understand why the other options are incorrect, we can look at their individual mechanisms. Lugol's iodine and radioactive iodine are both forms of iodine that can affect thyroid function, but they are not the only substances that can cause goiter through overtreatment. Carbimazole, as mentioned earlier, is a medication that can also result in goiter if misused. In an educational context, it is crucial for students to grasp the potential consequences of overtreatment with thyroid inhibitors, as this knowledge is essential for healthcare professionals working with patients with thyroid disorders. Understanding the side effects and proper dosages of these medications is vital for providing safe and effective care to individuals with thyroid conditions.