A patient who has advanced cancer is receiving opioid medications around the clock to 'keep him comfortable' as he nears the end of his life. Which term best describes this type of therapy?

Correct Answer: A

Rationale: Palliative therapy focuses on relieving symptoms and improving quality of life for patients with serious or life-limiting illnesses, such as advanced cancer. The goal is not to cure the disease but to provide comfort and alleviate suffering. In this case, the patient is receiving opioids around the clock to manage pain and ensure comfort, which is a hallmark of palliative care. Maintenance therapy is used to sustain a patient's condition, supportive therapy addresses specific symptoms, and supplemental therapy provides additional treatment. Therefore, palliative therapy is the most appropriate term for this scenario.

Correct Answer: A

Rationale: Overdose fatality depends on toxicity and mechanism. Amitriptyline, a tricyclic antidepressant (TCA), blocks sodium channels and muscarinic receptors, causing lethal arrhythmias, seizures, and anticholinergic effects (LD50 ~13 mg/kg), making it highly fatal. Fluoxetine, fluvoxamine, paroxetine, and citalopram, all SSRIs, primarily cause serotonin syndrome or seizures, but lethality is lower (e.g., citalopram's QT risk is less immediate). TCAs' cardiotoxicity far exceeds SSRIs', driving amitriptyline's higher fatality rate, a critical factor in prescribing for depression with suicide risk.

Correct Answer: C

Rationale: Insulin acts via tyrosine kinase receptors, not G-protein-coupled receptors, so that's false. Mineralocorticoids (e.g., aldosterone) bind intracellular receptors, not tyrosine kinase, making that incorrect. Vitamin D binds intracellular nuclear receptors, regulating gene transcription, a true statement and the correct pathway. Adrenaline acts via G-protein-coupled adrenergic receptors, not ligand-gated channels, so that's false. Platelet-derived growth factor uses tyrosine kinase, not cytokine receptors. Vitamin D's intracellular action is key to its role in calcium homeostasis, distinguishing it from membrane-bound receptor mechanisms.

Correct Answer: D

Rationale: Androgen therapy in men, typically testosterone replacement, aims to boost libido and treat erectile dysfunction by restoring normal androgen levels, countering hypogonadism's effects like reduced sexual drive. Decreasing libido contradicts its purpose, as low testosterone already dims desire. It doesn't release follicle-stimulating hormone (FSH)-exogenous androgens may suppress FSH and LH via feedback inhibition. Increasing luteinizing hormone (LH) isn't the goal; therapy bypasses LH by directly providing testosterone. Raising libido aligns with correcting symptoms of androgen deficiency, improving quality of life and sexual function, a primary clinical indication supported by its action on androgen receptors in sexual tissues.

Correct Answer: A

Rationale: Biliary excretion (e.g., rifampin) can prolong a drug's action via enterohepatic recycling-reabsorption from the gut extends duration, a key assessment point. Side effects don't inherently increase or decrease-dose and metabolism matter. Reduced effect assumes loss, not recycling. Prolonged action reflects pharmacokinetics, guiding monitoring for efficacy and toxicity.