Tolerance is associated with:

Correct Answer: D

Rationale: The correct answer is D because tolerance involves multiple mechanisms. A is correct because tolerance can involve compensating for the drug effect. B is correct because chronic use can lead to increased drug disposition. C is correct because tolerance can result from changes in receptors, enzymes, or membrane actions. Therefore, all of the above (A, B, and C) are associated with tolerance, making option D the correct answer. Each option individually addresses a different aspect of tolerance mechanisms, making them incorrect as standalone choices.

Correct Answer: A

Rationale: The correct answer is A: Papaverine. Papaverine is a smooth muscle relaxant, hence it decreases gastrointestinal motility. Metoclopramide, Domperidone, and Cisapride are prokinetic agents that stimulate gastrointestinal motility. Papaverine stands out as the exception due to its muscle-relaxing properties.

Correct Answer: C

Rationale: The correct answer is C: A decrease in preload. Preload refers to the volume of blood in the ventricles at the end of diastole, which affects the stretch of the myocardial fibers before contraction. In heart failure, preload is typically increased due to volume overload, not decreased. A cardiac lesion impairing cardiac output (A) is a common cause of heart failure. An increase in peripheral vascular resistance (B) can contribute to the pathogenesis by increasing afterload. An increase in sodium and water retention (D) is associated with volume overload and exacerbates heart failure symptoms. In summary, a decrease in preload is not normally involved in the pathogenesis of heart failure, making it the correct choice.

Correct Answer: C

Rationale: The correct answer is C because lidocaine can cause adverse reactions such as hypotension, paresthesias, and convulsions due to its effects on the central nervous system. Extrapyramidal disorders can also occur. A: Agranulocytosis and B: Leucopenia are not characteristic adverse reactions of lidocaine. D: Bronchospasm and dyspepsia are not typically associated with lidocaine use. Therefore, the correct choice is C as it aligns with lidocaine's known adverse reactions.

Correct Answer: B

Rationale: Rationale: Hydralazine is known to cause tachycardia as a side effect due to its vasodilatory properties. Lupus erythematosus can also be induced by hydralazine through its autoimmune effects. Seizures, extrapyramidal disturbances, acute hepatitis, and aplastic anemia are not typically associated with hydralazine use. Thus, option B is the correct choice.