Prometric Questions - Yellow File - MOH | SPLE | HAAD | DHA - 23

Which of the following can the pharmacological property of hydralazine be directly responsible for?
A)Relaxation of cardiac muscle
B)Blockade of dopamine receptor 
C)Relaxation of vascular smooth muscle
D)Contraction of vascular smooth muscle

The correct answer is C) Relaxation of vascular smooth muscle.

Hydralazine is a direct-acting vasodilator primarily used to treat hypertension (high blood pressure) and heart failure.

How Hydralazine Works

Hydralazine acts specifically on the arteriolar smooth muscle. While its exact cellular mechanism is still a bit of a pharmacological mystery, it is known to interfere with calcium movement within the muscle cells.

By preventing calcium from triggering a contraction, the medication causes the blood vessels to relax and widen. This results in:

• Decreased Peripheral Resistance: It’s easier for blood to flow through the "pipes."

• Decreased Blood Pressure: Because the resistance is lower, the pressure within the system drops.

Why the other options are incorrect:

• A) Relaxation of cardiac muscle: Hydralazine doesn't relax the heart; in fact, it often causes reflex tachycardia (a faster heart rate) because the body tries to compensate for the sudden drop in blood pressure.

• B) Blockade of dopamine receptors: This is the property of antipsychotics  not blood pressure medications.

• D) Contraction of vascular smooth muscle: This would be the effect of a vasoconstrictor (like adrenaline/epinephrine), which would increase blood pressure—the opposite of what hydralazine is designed to do.

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Clinical "Watch Out": Lupus-Like Syndrome

One unique side effect of hydralazine that often appears on exams is drug-induced lupus erythematosus. Patients may develop a butterfly rash, joint pain, and fever, which usually go away once the medication is stopped.

Quick Comparison

Drug	Action	Primary Target
Hydralazine	Vasodilator	Arteries
Nitroglycerin	Vasodilator	Veins (mostly)
Prazosin	Alpha-Blocker	Arteries & Veins

Which of the following statements best represents the inter venous (IV) medication in the hospital facilities? 

A)IV drugs transmits the highest risk of infection

B)IV drugs are associated with lowest risk of undesirability side effects

C)IV solutions must be hypotonic to ensure compatibility with blood osmolality

The correct answer is A) IV drugs transmit the highest risk of infection.

Intravenous (IV) administration bypasses the body’s most effective natural barriers—the skin and the digestive tract—placing the medication directly into the bloodstream.

Why Option A is Correct

Because the needle breaks the skin and the drug enters the systemic circulation immediately, any contamination (from the needle, the skin, or the solution itself) can lead to serious complications such as:

• Sepsis: A life-threatening systemic infection.

• Phlebitis: Inflammation of the vein.

• Abscesses: Localized pockets of infection at the injection site.

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Why the other options are incorrect:

B) Lowest risk of undesirable side effects

This is actually the opposite of the truth. IV drugs carry the highest risk of severe side effects because the drug reaches its peak concentration almost instantly. Unlike a pill, which can be pumped from the stomach if there is an error, an IV drug cannot be "taken back" once it is injected. This is often referred to as the "bolus effect."

C) IV solutions must be hypotonic

This is a dangerous misconception. To ensure compatibility with blood, IV solutions should generally be isotonic (having the same salt concentration as blood, roughly 0.9% NaCl).

• Hypotonic solutions can cause red blood cells to swell and burst (hemolysis).

• Hypertonic solutions can cause cells to shrivel (crenation).

Summary of IV Administration

Feature	Reality
Bioavailability	100% (Instant absorption)
Control	High (Easy to titrate/adjust dose)
Infection Risk	Highest (Direct blood access)
Cost	More expensive (Requires sterile equipment and trained staff)

A patient is to receive 400 ml intravenous infusion of a 1% drug that will be over 10 hours. Which of the following is the amount (milligrams)of the drug that will be delivered in 15 minutes? 
A)100 mg
B)150 mg
C) 200 mg
D) 400 mg

Correct answer: A) 100 mg

Step-by-step explanation:

1% solution = 1 g per 100 mL = 10 mg/mL

Total volume = 400 mL infused over 10 hours

Infusion rate = 400 mL ÷ 10 h = 40 mL/hour

15 minutes = 0.25 hour

Volume infused in 15 minutes: 40 mL/h × 0.25 h = 10 mL

Amount of drug delivered: 10 mL × 10 mg/mL = 100 mg

14 years-old man expressed withdrawal symptoms from using benzodiazepine drug which included irritability and aggression which of the following types of benzodiazepine is more likely associated with these symptoms?

A) long-acting benzodiazepines

B) ultra-short acting benzodiazepines 

C) benzodiazepines with active metabolites

D) benzodiazepines with high plasma protein binding

The correct answer is B) ultra-short acting benzodiazepines.

Withdrawal symptoms, especially psychological ones like irritability and aggression (often called "rebound symptoms"), are closely tied to how quickly a drug leaves the body.

Why Ultra-Short Acting Benzodiazepines?

The duration of action determines the "crash" the body experiences.

Rapid Decline: Ultra-short acting drugs (like Triazolam or Midazolam) are processed by the liver and cleared from the blood very quickly.

The "Cliff" Effect: Because the drug levels drop so abruptly, the brain's receptors—which have become dependent on the drug's calming effect—are suddenly left "starving." This leads to a more intense and immediate withdrawal syndrome.

Rebound Symptoms: Irritability, anxiety, and aggression are more common with these agents because the body doesn't have time to slowly adapt to the drug's absence.

Breakdown of the Other Options:

✖A) Long-acting benzodiazepines: These (like Diazepam) stay in the system for days. They provide a "natural taper," meaning the drug levels drop very slowly, making withdrawal symptoms much milder and delayed.

✖C) Active metabolites: Drugs with active metabolites (like Flurazepam) stay in the body longer as the metabolites continue to work even after the parent drug is gone. This acts similarly to a long-acting drug and usually reduces the severity of immediate withdrawal.

✖D) High plasma protein binding: This relates to how the drug travels in the blood, but it isn't the primary factor in the intensity of withdrawal symptoms.

Comparison of Withdrawal Severity

Benzodiazepine Type	Examples	Withdrawal Onset	Severity
Ultra-Short/Short	Triazolam, Alprazolam	Within hours	Severe / Intense
Long-Acting	Diazepam, Chlordiazepoxide	Days later	Mild / Gradual

Note for Clinical Context: In a 14-year-old, the use of benzodiazepines is handled with extreme caution due to the developing brain and the high risk of dependence. Management usually involves a very slow taper using a long-acting agent to avoid the exact symptoms mentioned in the question.

Which of the following drugs passes into mothers milk due to high lipid solubility? 

A)diazepam

B) methyldopa 

C) promethazine 

D) dihydroergotamine

The correct answer is A) diazepam.

When evaluating whether a drug will pass into breast milk, pharmacologists look for three main "green lights": high lipid (fat) solubility, low molecular weight, and low protein binding.

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Why Diazepam?

Breast milk has a significant fat content. Because diazepam is highly lipophilic (lipid-soluble), it easily dissolves across the lipid membranes of the mammary glands and concentrates in the fatty portion of the milk.

• Lipid Solubility: This is the primary driver for diazepam. It "likes" fat, so it moves readily into the milk.

• The "Floppy Baby" Risk: Because diazepam passes so effectively and has a long half-life, it can accumulate in the infant, leading to sedation, poor feeding, and "floppy infant syndrome" (neonatal hypotonia).

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Breakdown of the Options:

• A) Diazepam (Correct): Highly lipid-soluble; passes easily into milk and can cause sedation in the nursing infant.

• B) Methyldopa: While it can be found in milk, it is much less lipid-soluble than diazepam and is generally considered safe to use for hypertension during breastfeeding.

• C) Promethazine: While it has some lipid solubility, it is not the classic example used in pharmacology exams to demonstrate high lipid-solubility-driven milk transfer compared to benzodiazepines.

• D) Dihydroergotamine: This drug is actually contraindicated during breastfeeding, but for a different reason—it can suppress milk production (prolactin inhibition) and may cause vomiting or convulsions in the infant, regardless of its solubility.

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Factors Increasing Milk Transfer

Factor	Effect on Transfer
Lipid Solubility	High solubility = High transfer
Molecular Weight	Small molecules (<200 Da) pass more easily
Protein Binding	High binding in mother's blood = Lower transfer
pH (Ion Trapping)	Weakly basic drugs concentrate more in (slightly acidic) milk

Prometric Questions - Yellow File - MOH | SPLE | HAAD | DHA - 22

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