When a medication is added to a regimen for a synergistic effect, the combined effect of the drugs is:

Correct Answer: B

Rationale: The correct answer is B: Greater than the sum of the effects of each drug individually. When two drugs have a synergistic effect, they enhance each other's actions, leading to a combined effect that is more potent than what would be expected by simply adding their individual effects. This occurs due to the drugs targeting different pathways or mechanisms, resulting in increased efficacy. In contrast, option A (The sum of the effects of each drug individually) is incorrect because synergy implies an interaction beyond mere addition. Option C (Less than the effect of each drug individually) is incorrect as synergy typically leads to enhanced effects. Option D (Not predictable) is incorrect because synergy can be anticipated based on the mechanisms of action of the drugs involved.

Correct Answer: B

Rationale: The correct answer is B: When the amount of drug in the body remains constant. Steady state is achieved when the rate of drug administration equals the rate of drug elimination, leading to a constant drug concentration in the body. Option A is incorrect as it only refers to absorption and excretion, not overall drug levels. Option C is incorrect as it specifically mentions the maximum tolerated concentration, which is not necessarily related to steady state. Option D is incorrect as it includes all options, which are not all true statements about steady state.

Correct Answer: C

Rationale: Rationale: 1. Phase I metabolism involves enzymes like cytochrome P450, requiring proteins as cofactors. 2. Protein malnutrition reduces enzyme production, hindering the oxidative-reductive process. 3. Iron is necessary for cytochrome P450 activity, so iron deficiency impairs drug metabolism. 4. Option C is correct as both protein malnutrition and iron deficiency inhibit Phase I metabolism. Summary: - Choice A is incorrect because protein malnutrition affects enzyme production. - Choice B is incorrect because iron deficiency hampers cytochrome P450 activity. - Choice D is incorrect as both elements are essential for Phase I drug metabolism.

Correct Answer: D

Rationale: The correct answer is D because drug antagonism refers to the situation where one drug diminishes the effect of another drug when taken together. This occurs when the drugs have opposing actions on the body or compete for the same receptors. In contrast: A: Major physiological psychological dependence is related to addiction, not drug antagonism. B: The modification of drug effects by concurrent administration of another drug is known as drug interaction, not antagonism. C: The ability to be metabolized before another dose is administered is not related to drug antagonism.

Correct Answer: D

Rationale: The correct answer is D, Glucose. Glucose is a small molecule that is primarily absorbed in the small intestine through active transport mechanisms, where most nutrient absorption occurs. The small intestine has a larger surface area and more specialized transport mechanisms for nutrient absorption compared to the stomach. A, Sodium bicarbonate, is mainly absorbed in the stomach as it helps neutralize stomach acid. B, Ascorbic acid, is primarily absorbed in the stomach and the small intestine. C, Salicylic acid, is absorbed in the stomach and upper small intestine. Therefore, D is the most likely substance to be absorbed in the intestines rather than the stomach.