Which factor(s) affect(s) drug actions? (Select all that apply.)

Correct Answer: A

Rationale: The correct answer is A: Teratogenicity. Teratogenicity refers to the ability of a drug to cause harm to a developing fetus. This factor is crucial in determining drug actions because drugs can have different effects on pregnant women and their unborn babies. Age (B), body weight (C), and metabolic rate (D) can influence drug actions, but they do not directly address the impact on a developing fetus, unlike teratogenicity. Thus, A is the correct choice as it specifically relates to the potential harm drugs can cause during pregnancy.

Correct Answer: A

Rationale: The correct answer is A: Amphotericin B. This drug is known to cause abnormal lab results such as electrolyte imbalances (specifically hypokalemia), kidney dysfunction, and liver enzyme elevations due to its nephrotoxic and hepatotoxic effects. Amphotericin B is a potent antifungal medication used for severe fungal infections. Incorrect Choices: B: Fluconazole is less likely to cause significant abnormalities in lab results compared to Amphotericin B. C: Griseofulvin is not associated with the same degree of nephrotoxic and hepatotoxic effects as Amphotericin B. D: Flucytosine is not typically known for causing electrolyte imbalances or liver/kidney dysfunction like Amphotericin B.

Correct Answer: C

Rationale: Step 1: Fluconazole is metabolized by fungal cytochrome P-450 enzymes. Step 2: Gene-induced changes in these enzymes can lead to decreased drug efficacy. Step 3: Resistance to fluconazole commonly involves alterations in cytochrome P-450 enzymes. Step 4: Therefore, gene-induced changes in fungal cytochrome P-450 enzymes are most likely the mechanism of resistance in this patient. Summary: A is incorrect as topoisomerase II is not a target of fluconazole. B is incorrect as increased metabolism would not lead to resistance. D is incorrect as decreased activity of multiefflux pump would increase drug accumulation, not resistance.

Correct Answer: D

Rationale: The correct answer is D, "All of the above." Enalapril, Lisinopril, and Losartan are all medications known as ACE inhibitors or ARBs, which work by relaxing blood vessels and reducing the workload on the heart, thus effectively treating hypertension. Enalapril and Lisinopril are ACE inhibitors, while Losartan is an ARB. These medications help lower blood pressure by blocking certain enzymes or receptors, leading to vasodilation and decreased cardiac workload. Therefore, all three choices are correct as they all target the same mechanism of action in treating hypertension.

Correct Answer: B

Rationale: The correct answer is B: Stimulating beta-2 adrenergic receptors in the lungs. Albuterol is a beta-2 adrenergic agonist, which means it binds to and activates beta-2 adrenergic receptors in the lungs. By stimulating these receptors, albuterol causes smooth muscle relaxation, leading to bronchodilation and improved airflow in the lungs. This mechanism of action is beneficial in treating asthma by relieving bronchospasms and symptoms of shortness of breath. Choice A is incorrect because albuterol does not inhibit histamine release from mast cells. Choice C is incorrect as albuterol does not increase acetylcholine release in the lungs; in fact, it has the opposite effect by promoting bronchodilation. Choice D is incorrect as albuterol does not block leukotriene receptors; leukotriene receptor antagonists like montelukast are used for that purpose.