Benzodiazepine

Question 1

What is the half-life of midazolam, lorazepam, and diazepam?

Answer 1

Midazolam: 1.5-3.5 hours
Lorazepam: Twice that of midazolam
Diazepam: 20-50 hours

Question 2

What factors increase the half-life of midazolam, lorazepam, and diazepam?

Answer 2

Midazolam: Elderly, obese, cirrhotic patients, CYP450 inhibitors, opioids
Lorazepam: Obesity, enterohepatic circulation (not affected by age, cirrhosis, or CYP450 inhibitors)
Diazepam: Elderly, obese, cirrhotic patients, CYP450 inhibitors, enterohepatic recirculation

Question 3

How does long-term sedation affect the half-life of midazolam, lorazepam, and diazepam?

Answer 3

Midazolam: Increases to 1.5-50 hours
Lorazepam: Increases by 30%
Diazepam: Extended half-life

Question 4

What are the active metabolites of midazolam, lorazepam, and diazepam?

Answer 4

Midazolam: 1- and 4-hydroxymidazolam
Lorazepam: None, but has enterohepatic recirculation
Diazepam: Desmethyl-diazepam, oxazepam

Question 5

What is the onset time of midazolam, lorazepam, and diazepam?

Answer 5

Midazolam: 30 sec - 1 min
Lorazepam: 1-2 minutes
Diazepam: Within 60 seconds

Question 6

When do midazolam, lorazepam, and diazepam reach peak effect?

Answer 6

Midazolam: 3-5 minutes
Lorazepam: 20-30 minutes
Diazepam: 3-4 minutes

Question 7

How long is the duration of action for midazolam, lorazepam, and diazepam?

Answer 7

Midazolam: 15-80 minutes
Lorazepam: 6-10 hours
Diazepam: 1-6 hours

Question 8

How long does emergence take from a single bolus of midazolam, lorazepam, and diazepam?

Answer 8

Midazolam: 20 minutes
Lorazepam: 55 minutes
Diazepam: 10 minutes

Question 9

How long does emergence take from light continuous sedation for midazolam, lorazepam, and diazepam?

Answer 9

Midazolam: 4.5 hours
Lorazepam: 13 hours
Diazepam: 31 minutes

Question 10

How long does emergence take from deep sedation for midazolam, lorazepam, and diazepam?

Answer 10

Midazolam: 15.5 hours
Lorazepam: 32 hours
Diazepam: 24 hours

Question 11

How do the amnestic properties of midazolam, lorazepam, and diazepam compare?

Answer 11

Midazolam: Twice as potent as diazepam; amnesia lasts up to 24 hours after sedation wears off
Lorazepam: One-quarter the potency of midazolam, but effects last for days
Diazepam: More amnestic effects than sedative effects

Question 12

What are the induction doses for midazolam, lorazepam, and diazepam?

Answer 12

Midazolam: 2-5 mg
Lorazepam: 1-4 mg
Diazepam: 10 mg

Question 13

What are the alternative route doses for midazolam?

Answer 13

Nasal: 0.2-0.3 mg/kg
Oral: 1 mg/kg