What percentage of valproic acid was most likely lipid soluble in the patient's duodenal lumen?

Correct Answer: B

Rationale: In pharmacology, understanding the lipid solubility of drugs is crucial as it affects their absorption, distribution, and overall pharmacokinetics. Valproic acid is a highly lipophilic compound, meaning it has a strong affinity for lipid-rich environments like cell membranes. Option B (24%) is the correct answer because valproic acid is estimated to be about 24% lipid soluble in the patient's duodenal lumen. This significant lipid solubility enhances its absorption in the small intestine, leading to better bioavailability and therapeutic effects. Option A (1%) is too low to account for valproic acid's known lipophilicity, which would result in poor absorption and reduced efficacy of the drug. Option C (50%) is too high as it overestimates the lipid solubility of valproic acid. While it is indeed lipophilic, it is not as soluble in lipids as some other drugs. Option D (76%) is also too high. While valproic acid is lipid-soluble, a percentage as high as 76% would be excessive and not reflective of its actual properties. Educationally, this question highlights the importance of understanding drug properties like lipid solubility in pharmacology. It reinforces the concept that drug absorption and distribution are influenced by their chemical characteristics, which in turn impact their therapeutic effectiveness. Students need to grasp these principles to make informed decisions in drug therapy and patient care.

Correct Answer: D

Rationale: The term that describes a characteristic of loratadine binding to the H receptor is affinity. Affinity refers to the strength of the binding between a drug and its receptor, indicating how well the drug molecule fits into the receptor site. In the case of loratadine binding to the H receptor, affinity plays a crucial role in determining the drug's effectiveness in treating seasonal rhinitis.

Correct Answer: B

Rationale: In this question, the correct answer is B) Tachyphylaxis. Tachyphylaxis refers to a rapid decrease in response to a drug after repeated doses over a short period. This term specifically describes the phenomenon of rapidly diminishing effect with repeated administration rather than a gradual decrease over time. Option A) Cross-tolerance refers to a situation where tolerance to one drug leads to a reduced response to another drug, usually of a similar class. This term does not accurately describe the pattern mentioned in the question. Option C) Pharmacokinetic tolerance is related to changes in the absorption, distribution, metabolism, or excretion of a drug leading to reduced effectiveness. This term focuses on the body's processing of the drug rather than the rapid decrease in response indicated in the question. Option D) Innate tolerance would imply a natural or inherent resistance to a drug, which is different from the acquired tolerance pattern described in the question. Educationally, understanding these different types of tolerance patterns is crucial in pharmacology to optimize drug therapy and avoid potential adverse effects. Recognizing the specific characteristics of each type of tolerance can guide healthcare professionals in making informed decisions regarding dosing regimens and treatment strategies for patients.

Correct Answer: D

Rationale: The most likely time lapse expected between receptor activation and therapeutic response in this scenario would be one or two hours. This is because synthetic steroids usually act on intracellular receptors, which typically require some time to produce a therapeutic effect. The delay is due to the need for gene transcription and protein synthesis to occur in order to elicit the desired response. Therefore, the time frame of one to two hours aligns with the expected mechanism of action of synthetic steroids.

Correct Answer: A

Rationale: The correct answer is A, Type I allergic reaction. This is because the patient developed symptoms of an anaphylactic-like reaction after exposure to vancomycin, despite not having previous exposure or antibodies to the drug. This type of reaction is typically immediate and involves the immune system's response to the drug, leading to symptoms such as hives, swelling, and difficulty breathing.