Nokea
Which antibiotic is primarily bacteriostatic but becomes bactericidal at higher concentrations?:
- A. Erythromycin
- B. Tetracycline
- C. Chloramphenicol
- D. Ampicillin
Correct Answer: A
Rationale: Erythromycin is primarily bacteriostatic by inhibiting protein synthesis in bacteria. At higher concentrations, it can disrupt bacterial cell membranes, making it bactericidal. Tetracycline inhibits protein synthesis, Chloramphenicol blocks peptide bond formation, and Ampicillin disrupts bacterial cell wall synthesis. Therefore, A is correct because of its dual mechanism of action.
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Which statement best describes Zidovudine: *
- A. Zidovudine in combination with other antiretrovirals is an alternative initial treatment for HIV infection.
- B. Zidovudine is also used to prevent transmission of HIV from the mother to her
- C. Zidovudine is converted by cellular enzymes to an active form, zidovudine diphosphate, which prevents viral DNA from replicating.
- D. Peripheral neuropathy is a specic adverse reaction to Zidovudine
Correct Answer: C
Rationale: Rationale for Correct Answer (C):
1. Zidovudine is a nucleoside reverse transcriptase inhibitor (NRTI) used in the treatment of HIV.
2. Zidovudine is indeed converted by cellular enzymes to its active form, zidovudine diphosphate.
3. Zidovudine diphosphate inhibits the reverse transcriptase enzyme, preventing viral DNA replication in HIV-infected cells.
4. This mechanism of action is crucial in reducing viral load and slowing disease progression in HIV patients.
Summary of Incorrect Choices:
A: Incorrect. While Zidovudine is used in combination therapy for HIV, it is not typically an alternative initial treatment.
B: Incorrect. Zidovudine can be used to prevent mother-to-child transmission of HIV, but it is not its primary indication.
D: Incorrect. Peripheral neuropathy is not a specific adverse reaction to Zidovudine; rather, it is more commonly associated with
A physician is caring for a patient with a urinary tract infection. The physician would expect the plan of care to include:
- A. Antibiotics and phenazopyridine.
- B. Erythropoietin and stent placement.
- C. Hormonal therapy and intravenous fluids.
- D. Hourly urine output measurements and antibiotics.
Correct Answer: A
Rationale: The correct answer is A: Antibiotics and phenazopyridine. Antibiotics are essential to treat the bacterial infection causing the UTI. Phenazopyridine can help relieve urinary discomfort. Erythropoietin and stent placement (B) are not indicated for UTI. Hormonal therapy and IV fluids (C) are not standard treatments for UTI. Hourly urine output measurements and antibiotics (D) are not typically necessary, as antibiotics alone are sufficient for treating UTIs.
A patient was treated with digoxin and he develop signs and symptoms of * digoxin toxicity caused by furosemide therapy. What did the diuretic most likely do to precipitate the digoxin toxicityy?
- A. caused by hypocalcemia
- B. caused by hypo natremia
- C. caused by hypokalemia
- D. None of the above
Correct Answer: C
Rationale: The correct answer is C: caused by hypokalemia. Furosemide, a loop diuretic, can lead to potassium loss (hypokalemia), which can exacerbate digoxin toxicity. Low potassium levels increase the risk of digoxin binding more strongly to cardiac tissue, leading to toxicity symptoms. Hypocalcemia (A) and hyponatremia (B) are not directly related to digoxin toxicity, making them incorrect choices. Choice D is incorrect as hypokalemia is a known risk factor for digoxin toxicity.
For which patient with incontinence would a bladder-training program be an appropriate intervention?
- A. The patient with functional incontinence due to mental status changes
- B. The patient with stress incontinence due to weakened bladder neck support
- C. The patient with urge incontinence and abnormal detrusor muscle contractions
- D. The patient with transient incontinence due to inability to get to toileting facilities
Correct Answer: C
Rationale: The correct answer is C: the patient with urge incontinence and abnormal detrusor muscle contractions. Bladder training is an appropriate intervention for this patient because it aims to increase the bladder capacity and decrease the frequency of abnormal contractions. The program involves scheduled voiding and delaying urination to gradually increase the time between bathroom visits. This helps to retrain the bladder muscles and improve control over urination.
A: Functional incontinence due to mental status changes is not typically addressed through bladder training.
B: Stress incontinence due to weakened bladder neck support is better treated with pelvic floor exercises and lifestyle modifications.
D: Transient incontinence due to inability to get to toileting facilities requires environmental modifications and timed toileting, not bladder training.
The most frequent side effect of oral ampicillin is : *
- A. Nausea and vomiting
- B. Loose bowel movements
- C. Constipation
- D. Urticaria
Correct Answer: A
Rationale: The correct answer is A: Nausea and vomiting. Oral ampicillin commonly causes gastrointestinal side effects such as nausea and vomiting due to its impact on the gut flora. This side effect is a result of the antibiotic's mechanism of action and is well-documented in clinical practice. Choices B, C, and D are incorrect as loose bowel movements, constipation, and urticaria are not typically associated with oral ampicillin use.