A patient with benign prostatic hypertrophy (BPH) has been prescribed prazosin (Minipress) and asks the nurse what this is going to do for him. The nurse’s response will include what action to explain the purpose of taking this medication?

Correct Answer: C

Rationale: Alpha1-selective adrenergic blocking agents block smooth muscle receptors in the prostate, prostatic capsule, prostatic urethra, and urinary bladder neck, which leads to a relaxation of the bladder and prostate and improved flow of urine in male patients. Although they also block the postsynaptic alpha1-receptor sites, causing a decrease in vascular tone and vasodilation that leads to a fall in blood pressure without the reflex tachycardia that occurs when the presynaptic alpha2-receptor sites are blocked, this is not the purpose for administering the drug to a patient with BPH. They do not reduce the size of the prostate.

Correct Answer: C

Rationale: Alpha1-selective adrenergic blocking agents block smooth muscle receptors in the prostate, prostatic capsule, prostatic urethra, and urinary bladder neck, which leads to a relaxation of the bladder and prostate and improved flow of urine in male patients. Although they also block the postsynaptic alpha1-receptor sites, causing a decrease in vascular tone and vasodilation that leads to a fall in blood pressure without the reflex tachycardia that occurs when the presynaptic alpha2-receptor sites are blocked, this is not the purpose for administering the drug to a patient with BPH. They do not reduce the size of the prostate.

Correct Answer: B

Rationale: Theophylline overdose (empty bottle) causes cardiac arrhythmias . Toxicity leads to tachyarrhythmias, often fatal. Apnea is secondary. Pulmonary embolism lacks context. Seizures occur but aren't primary. Tetany (E) is unrelated. Arrhythmias align with theophylline's narrow therapeutic index.

Correct Answer: D

Rationale: Acute asthma and pneumonia in pregnancy require urgent care. IV crystalloids rehydrate, safe and necessary. High FiO2 (40%) supports oxygenation in asthma/pneumonia, appropriate. Nebulized salbutamol, a beta-agonist, relieves bronchospasm, standard and safe. IV hydrocortisone reduces inflammation, suitable. IV gentamicin, an aminoglycoside, treats pneumonia but is inappropriate due to cephalosporin cross-reactivity risk (angioedema history) and fetal ototoxicity concerns, making it unsafe here. Alternative antibiotics (e.g., macrolides) are preferred, prioritizing maternal and fetal safety.

Correct Answer: D

Rationale: Loop diuretics, such as furosemide and bumetanide, work by inhibiting the sodium-potassium-chloride co-transporter in the thick ascending loop of Henle in the kidney. This mechanism of action leads to a significant diuretic effect. Loop diuretics have a rapid onset of action, typically within 30 minutes of administration, and they cause rapid diuresis. This rapid onset and potent diuretic effect make loop diuretics effective in situations requiring rapid removal of excess fluid, such as heart failure exacerbation or acute pulmonary edema.

Correct Answer: B

Rationale: In a hypertensive emergency where a patient's blood pressure is extremely elevated (such as 270/150 mm Hg in this case), one of the medications commonly used is a titratable intravenous antihypertensive medication like nicardipine. The maximum dose of nicardipine that should be infused is typically guided by the patient's response to treatment and not a fixed duration of time. Therefore, the correct answer is B, as it highlights the importance of titrating the medication based on the patient's blood pressure response, rather than a specific time frame for infusion. Utilizing the drug at the lowest effective dose is crucial to avoid potential adverse effects, especially in a hypertensive emergency scenario.

Correct Answer: C

Rationale: Phenolic germicidal agents are commonly used as disinfectants due to their ability to kill microorganisms. Hexachlorophene is one type of phenolic germicidal agent that has been used as a surgical scrub in the past. It has antiseptic properties and can effectively reduce the number of bacteria on the skin, making it suitable for use in sterile environments such as surgical procedures. While phenolic germicidal agents do possess antibacterial properties, they do not typically have topical anesthetic effects like some other types of disinfectants. Additionally, while phenolic agents are used in various dental procedures, they are not specifically used in root canal therapy. The examples provided in the last statement, formocresol, cresantin, and eugenol, are not phenolic germicidal agents but rather dental materials used for different purposes.

Correct Answer: A

Rationale: Rifampicin is a potent inducer of CYP450 enzymes, increasing the metabolism of drugs processed via these pathways.

Correct Answer: A

Rationale: Magnesium sulfate toxicity can cause respiratory depression, which is indicated by a respiratory rate of 10 breaths per minute or less. This is a life-threatening complication requiring immediate intervention. Deep tendon reflexes are typically absent in severe toxicity, not present. A urine output of 25 ml/hr may indicate renal impairment but is not specific to magnesium toxicity. A serum magnesium level of 7 mEq/L is elevated but does not alone confirm toxicity without clinical symptoms. Therefore, respiratory depression is the key indicator.