When a patient asks the nurse what hypersensitivity is, how should the nurse respond? Hypersensitivity is best defined as:

Correct Answer: C

Rationale: Hypersensitivity is correctly defined as an excessive or inappropriate response of the immune system to a sensitizing antigen. This response leads to tissue damage or other clinical manifestations. Choice A is incorrect as hypersensitivity involves an exaggerated, not a reduced, immune response. Choice B is incorrect because hypersensitivity is not a normal immune response to an infectious agent but rather an exaggerated one. Choice D is incorrect as it refers to desensitization, which is the opposite of hypersensitivity.

Correct Answer: C

Rationale: The correct answer is C: Serum sickness. Serum sickness is characterized by the formation of immune complexes in response to certain medications or proteins. These immune complexes can deposit in tissues, leading to inflammation and tissue damage. Bronchial asthma (Choice A) is a chronic inflammatory condition of the airways not primarily mediated by immune complexes. Contact dermatitis (Choice B) is a type IV hypersensitivity reaction mediated by T cells, not immune complexes. Rheumatoid arthritis (Choice D) is an autoimmune disease where antibodies target self-antigens, but it is not primarily mediated by immune complexes.

Correct Answer: B

Rationale: Swelling during acute inflammation is primarily caused by the accumulation of fluid exudate in the affected tissues. This fluid exudate contains proteins and cells that leak from blood vessels due to increased vascular permeability. Collagenase (Choice A) is an enzyme that breaks down collagen and is not directly responsible for swelling. Lymphocytic margination (Choice C) is the process where white blood cells line up along the blood vessel walls, which does not directly cause swelling. Anaerobic glycolysis (Choice D) is a metabolic process that occurs in the absence of oxygen and is not related to the mechanism of swelling in acute inflammation.

Correct Answer: B

Rationale: The correct answer is B: 'vigilant adherence to the drug regimen.' When initiating oral contraceptive therapy, the success of preventing pregnancy relies heavily on the patient's commitment to following the prescribed regimen consistently. Compliance with taking the oral contraceptives as directed is crucial for their effectiveness. Choice A, 'current health status,' is not the primary factor for successful prevention of pregnancy with oral contraceptives. Choice C, 'knowledge of sexual health,' while important, is not the primary determinant of contraceptive efficacy. Choice D, 'risk factors for adverse effects,' though relevant for monitoring and managing side effects, is not the primary focus for ensuring contraceptive success.

Correct Answer: B

Rationale: The correct answer is B. Finasteride (Proscar) is used in the treatment of benign prostatic hyperplasia to improve urinary flow and decrease symptoms of urinary retention by reducing the size of the prostate gland. Choice A is incorrect because although finasteride may reduce the size of the prostate gland, the expected outcome relevant to the patient's symptoms is improved urinary flow rather than a specific change in gland size. Choice C is incorrect because finasteride actually decreases the production of prostate-specific antigen (PSA) due to its mechanism of action. Choice D is incorrect because although improved urinary flow may lead to a reduction in nocturnal awakenings, the main expected outcome of finasteride treatment is related to urinary symptoms.