The cell and Coombs classification system categorizes allergic reactions and is useful in describing and classifying patient reactions to drugs. Type I reactions are immediate hypersensitivity reactions and are mediated by:

Correct Answer: A

Rationale: The correct answer is A: immunoglobulin E (IgE). IgE is responsible for mediating Type I immediate hypersensitivity reactions, such as allergic reactions. IgE binds to allergens and triggers the release of histamine and other inflammatory mediators from mast cells, leading to symptoms like hives and anaphylaxis. IgG (B), IgA (C), and IgM (D) are not typically involved in Type I allergic reactions. IgG is involved in Type II and Type III hypersensitivity reactions, IgA is related to mucosal immunity, and IgM is mainly involved in the primary immune response.

Correct Answer: D

Rationale: The correct answer is D: Cabergoline. Cabergoline is a dopamine agonist used to treat hyperprolactinemia. It is appropriate to add to therapy if the patient has hyperprolactinemia symptoms. Cosyntropin (A) is a synthetic ACTH used to test adrenal gland function. Mecasermin (B) is a recombinant IGF-1 used to treat growth hormone insensitivity. Leuprolide (C) is a GnRH agonist used to treat conditions like endometriosis and prostate cancer. None of these options are appropriate for hyperprolactinemia, making D the correct choice.

Correct Answer: A

Rationale: Step-by-step rationale for the correct answer (A: Pegvisomant): 1. Patient likely has acromegaly due to elevated growth hormone levels. 2. Pegvisomant is a growth hormone receptor antagonist used to treat acromegaly by blocking the effects of growth hormone. 3. This drug would be appropriate to normalize the patient's growth hormone levels and improve symptoms. Summary of why other choices are incorrect: - B: Degarelix is a gonadotropin-releasing hormone antagonist used in prostate cancer, not for acromegaly. - C: Leuprolide is a gonadotropin-releasing hormone agonist used in various conditions like prostate cancer and endometriosis, not for acromegaly. - D: Cosyntropin is a synthetic form of adrenocorticotropic hormone used in diagnostic testing for adrenal function, not for acromegaly treatment.

Correct Answer: C

Rationale: The correct answer is C: Methimazole. Methimazole is an antithyroid drug used to treat hyperthyroidism by inhibiting thyroid hormone synthesis. The results described are likely due to hyperthyroidism, which methimazole would help regulate. Radioactive iodine (A) is used to destroy thyroid tissue, potassium iodide (B) is used to protect the thyroid from radiation, and propranolol (D) is a beta-blocker used to manage symptoms but does not directly address thyroid hormone levels.

Correct Answer: B

Rationale: The correct answer is B: Sweating. Excessive dose of methimazole, an anti-thyroid medication used to treat Graves disease, can lead to increased sympathetic nervous system activity, causing hyperactivity of sweat glands and resulting in sweating. Palpitations (A) are more commonly associated with hyperthyroidism itself, rather than medication side effects. Insomnia (C) can be a symptom of hyperthyroidism but is not a direct effect of methimazole overdose. Tremor (D) is also a common symptom of hyperthyroidism, not a specific effect of methimazole overdose.