Benzodiazepines - Midazolam Flashcards
Potency:
› Lorazepam > Midazolam > Diazepam
› Lorazepam ~ 5 times more potent than Midazolam.
› Midazolam ~ 5 times more potent that Diazepam.
Which of the following statements about the Imidazole ring in Midazolam is correct?
A. The Imidazole ring opens at a physiological pH, increasing lipid solubility.
B. The Imidazole ring closes at an acidic pH, decreasing water solubility.
C. The Imidazole ring opens at an acidic pH, increasing water solubility.
D. The Imidazole ring remains unaffected by pH changes.
C. The Imidazole ring opens at an acidic pH, increasing water solubility.
What is the primary effect of Midazolam’s Imidazole ring closing at physiological pH?
A. Increased water solubility
B. Increased lipid solubility
C. Decreased lipid solubility
D. Increased pH stability
B. Increased lipid solubility
For adult premedication, what is the recommended intravenous dose range for Midazolam?
A. 0.5-1 mg
B. 1-2 mg
C. 2-4 mg
D. 5-10 mg
B. 1-2 mg
When used for induction of anesthesia in adults, what is the typical dose range of Midazolam?
A. 0.05-0.1 mg/kg
B. 0.1-0.2 mg/kg
C. 0.2-0.3 mg/kg
D. 0.3-0.5 mg/kg
B. 0.1-0.2 mg/kg
What concentration of Midazolam is commonly available for intravenous administration?
A. 0.5 mg/mL
B. 1 mg/mL
C. 2 mg/mL
D. 5 mg/mL
Answer: B. 1 mg/mL
What is the primary mechanism of action of Midazolam?
A. NMDA receptor antagonist
B. GABAA receptor agonist
C. Dopamine receptor agonist
D. Serotonin receptor antagonist
B. GABAA receptor agonist
What effect does Midazolam have on the GABAA receptor?
A. Decreases the frequency of channel opening
B. Increases the frequency of channel opening
C. Blocks the channel completely
D. Inhibits receptor binding
B. Increases the frequency of channel opening
Which area of the brain does Midazolam primarily inhibit to induce sleep?
A. Cerebellum
B. Limbic system
C. Thalamic and mid-brain reticular activating system (RAS)
D. Basal ganglia
C. Thalamic and mid-brain reticular activating system (RAS)
What is the typical onset time for Midazolam when administered intravenously?
A. 30 seconds to 1 minute
B. 1-2 minutes
C. 2-5 minutes
D. 5-10 minutes
B. 1-2 minutes
What is the average duration of action for Midazolam, assuming normal hepatic clearance?
A. 30 minutes
B. 1 hour
C. 2 hours
D. 4 hours
B. 1 hour
What is the half-life of Midazolam in a healthy adult?
A. 1-2 hours
B. 2-4 hours
C. 4-6 hours
D. 6-8 hours
B. 2-4 hours
How does the half-life of Midazolam change in elderly patients compared to younger adults?
A. It is shorter
B. It remains the same
C. It is doubled
D. It is tripled
C. It is doubled
What percentage of Midazolam is bound to plasma proteins?
A. 50%
B. 70%
C. 85%
D. 97%
D. 97%
Which enzyme systems are primarily responsible for the metabolism of Midazolam?
A. CYP450 in the liver and intestines
B. Glucuronidase in the liver
C. Esterases in the plasma
D. Monoamine oxidase in the liver
A. CYP450 in the liver and intestines