In the fusion method of making cocoa butter suppositories, which substance is most likely to be used to lubricate the mold?

Correct Answer: A

Rationale: Mineral oil (A) is most likely used to lubricate molds in the fusion method for cocoa butter suppositories, preventing sticking and ensuring easy release post-cooling. Propylene glycol (B) is a humectant, not a lubricant. Cetyl alcohol (C) and stearic acid (D) are base components, not mold lubricants. Magnesium silicate (original E) is a filler, not suitable. Mineral oil's inert, oily nature facilitates clean suppository production, maintaining shape and drug uniformity (e.g., bisacodyl), a practical step in extemporaneous compounding.

Correct Answer: A

Rationale: Acidic drugs mainly bind to albumin (A), the most abundant plasma protein, with sites for weak acids (e.g., warfarin, ibuprofen), affecting free drug levels. α₁-acid glycoprotein (B) binds basic drugs (e.g., lidocaine). Option C is incorrect as acidic drugs favor albumin. Option D is false. This binding, reversible and saturable, reduces free drug for distribution, prolonging action but risking displacement interactions (e.g., with aspirin), a key pharmacokinetic factor in dosing and toxicity.

Correct Answer: B

Rationale: A large apparent volume of distribution (V_D) (B) is the earliest evidence of tissue storage, indicating drug distribution beyond plasma into tissues (e.g., digoxin, V_D > 500 L), calculated as dose/plasma concentration. Increased plasma binding (A) reduces V_D. Decreased metabolism (C) affects clearance, not distribution. Side effects (D) or reduced free drug (original E) are downstream. High V_D reflects lipophilicity or tissue affinity, guiding dosing (e.g., loading doses), critical in pharmacokinetics for drugs with extensive tissue uptake.

Correct Answer: A

Rationale: The rate of blood flow to tissue (A) chiefly determines initial drug distribution, as perfusion delivers drug to organs (e.g., brain > fat), seen in anesthetics' rapid onset. GFR (B) affects excretion, not distribution. Stomach emptying (C) influences absorption. Tissue affinity (D) and plasma binding (original E) shape later distribution. Perfusion-limited kinetics prioritize highly vascular tissues, critical for acute therapies, with redistribution (e.g., thiopental) altering duration, a fundamental pharmacokinetic principle.

Correct Answer: D

Rationale: Maltose (D) is not a polysaccharide; it's a disaccharide (glucose-glucose), hydrolyzed to monosaccharides, unlike polysaccharides heparin (A, anticoagulant), starch (B, plant storage), and glycogen (C, animal storage), which are large, branched polymers. Cellulose (original E) is also a polysaccharide. Maltose's smaller size, formed during starch digestion, contrasts with polysaccharides' complexity, impacting absorption speed and therapeutic use (e.g., heparin's long-acting effects), key in carbohydrate pharmacology.