ATI RN
Basic pharmacology principles Questions
Question 1 of 5
Animal testing of potential new therapeutic agents
Correct Answer: C
Rationale: The correct answer is that animal testing requires the submission of histopathologic slides and specimens to the FDA (C), part of preclinical data in the Investigational New Drug (IND) application, ensuring safety evaluation. Option A is false; testing duration varies (months to years), not fixed at 3 years. Option B is incorrect; two species (e.g., rodent and non-rodent like dog) are typical, not necessarily primates. Option D is wrong; allergy prediction is poor in animals due to immune differences. Option E (original) about abbreviation for toxic agents is true but less defining. This regulatory step validates toxicity and pharmacology data, bridging preclinical and human trials.
Question 2 of 5
Which mechanism is most often responsible for chemical degradation?
Correct Answer: C
Rationale: Hydrolysis (C) is the most common mechanism for chemical degradation, where water cleaves bonds (e.g., esters in aspirin to salicylic acid), accelerated by pH or enzymes. Racemization (A) alters chirality (e.g., thalidomide), less frequent. Photolysis (B) degrades via light (e.g., nitroprusside), context-specific. Decarboxylation (D) removes COâ‚‚ (e.g., levodopa), rarer. Oxidation (original E) affects drugs like morphine but is less universal. Hydrolysis's prevalence in aqueous environments drives stability testing, requiring protective packaging or formulation adjustments (e.g., dry powders) to extend shelf life.
Question 3 of 5
Rectal suppositories intended for adult use usually weigh approximately
Correct Answer: B
Rationale: Rectal suppositories for adults usually weigh approximately 2g (B), a standard size ensuring sufficient drug load (e.g., glycerin for constipation) and comfortable insertion. Options A (1g) and C (3g) are smaller/larger, less common, while D (4g) and original E (5g) are excessive for routine use. This weight balances efficacy, melting time, and patient tolerance, critical in suppository design for systemic (e.g., analgesics) or local effects, with cocoa butter or synthetic bases adjusting to body temperature for release.
Question 4 of 5
Nonionic surface-active agents used as synthetic emulsifiers include
Correct Answer: C
Rationale: Sorbitan esters (spans) (C) are nonionic surfactants used as synthetic emulsifiers, stabilizing emulsions (e.g., creams) by reducing surface tension without ionization. Tragacanth (A) is a natural gum, not synthetic. Sodium lauryl sulphate (B) is anionic, not nonionic. Option D is a placeholder. No original E exists. Spans' lipophilic nature (low HLB) aids oil-in-water emulsions, enhancing drug delivery and stability, widely used in topical and oral pharmaceuticals for their versatility.
Question 5 of 5
The route of drug administration that gives the most rapid onset of the pharmacological effect is
Correct Answer: B
Rationale: Intravenous injection (B) gives the most rapid onset, delivering drug directly into the bloodstream, bypassing absorption (e.g., morphine in seconds). Intramuscular (A) and subcutaneous (original E) are slower due to tissue absorption. Intradermal (C) is slowest, for local effects. Peroral (D) involves GI absorption, delaying onset (e.g., 30-60 min). IV's immediacy suits emergencies, avoiding first-pass metabolism, though it risks rapid toxicity, requiring precise dosing and monitoring.