Week 4 - Pharmacology; Benzodiazepines

Question 1

Why are benzos commonly prescribed?

Answer 1

• minimal tolerance or physical dependence

note it is a drug class

Question 2

What is the MOA of benzodiazepines? (3)

Answer 2

• depress CNS activity
• Affect hypothalamic, thalamic, and limbic systems of the brain
• potentiates the inhibitory effects of endogenous GABA

Question 3

What occurs during withdrawal of benzodiazepines? (6)

Answer 3

• insomnia
• anxiety
• agitation
• tremor
• tachycardia
• anorexia

Question 4

Why can benzos be good? (2)

Answer 4

• less REM sleep suppression
• does not increase metabolism of other drugs

Question 5

What is diazepam? (4)

Answer 5

• valium
• long-acting
• PO route
  Dose: 0.5-2 mg/h
• half life 100h

Question 6

What is lorazepam? (5)

Answer 6

• Ativan
• intermediate acting
• PO route
  Dose: 2-4 mg/h
• half life 10-20 hours

Question 7

What is the route and frequency for sublingual and IV lorazepam?

Answer 7

sl - 1 hr
IV - 5-10 min

Question 8

What is midazolam? (5)

Answer 8

• versed
• IV route
• short-acting
  dose: 1.5-5mg/min
• half life 1-4 hours

Question 9

What are other drugs that are short acting? (3)

Answer 9

• temazepam (restoril)
• alprazolam (xanax)
• triazolam (halcion)

Question 10

Which benzodiazepine would you use for alcohol withdrawal?

Answer 10

diazepam

Question 11

Which routes are preferred for benzos?

Answer 11

• PO/SL route

Question 12

Why are IV doses of benzos not preferred? 92)

Answer 12

• may have profound BP drop (cardiac arrest) and/or respiratory depression (resp. arrest)
• have emergency equipment nearby

Question 13

What happens with a mild overdose of benzos? (4)

Answer 13

• drowsiness
• Impaired coordination
• confusion
• lethargy

Question 14

What happens with a serious overdose of benzos? (5)

Answer 14

• ataxia
• hypotonia
• hypotension
• resp. depression
• coma

Question 15

What happens with a rare overdose of benzos?

Answer 15

• cardiac arrest when combined with alcohol or other CNS depressants

Question 16

What drug is used for a benzodiazepine overdose?

Answer 16

• flumazenil used for reversal

Question 17

What is flumazenil? (3)

Answer 17

• used to reverse sedative effects during minor procedures
• useful, if no long-term use of BZD, otherwise withdrawal
• effect fades in 1h (repeat doses may be necessary)

Question 18

Do BZDs induce hepatic drug-metabolizing enzymes?

Answer 18

no

Question 19

Can you take BZD with other CNS depressants like alcohol or opiods?

Answer 19

no
- risk for respiratory depression

Question 20

What do enzyme inducers do to BZDs? (2)

Answer 20

• reduce the effect of Benzo by speeding its breakdown
  ex. carbamazepine, phenobarbital, phenytoin, St John’s wort (herbal for depression)

Question 21

What do enzyme inhibitors do to BZDs? (2)

Answer 21

• increase the effect of Benzo by delaying breakdown
  ex. grapefruit (diazepam), diltiazem, verapamil, macrolide, antibiotics, fluconazole, omeprazole, oral contraceptives

Question 22

Another sedative-hypnotic is zopiclone. What is that? (2)

Answer 22

• PO
  -short term use for insomnia
• addictive and can build tolerance

Question 23

How do we assess LOC and sedating drugs? (7)

Answer 23

1. Monitoring patients we have been sedating with drugs
2. Monitor during sedation - and to track recovery
3. respiration (deep/cough, dyspnea/shallow, apnea)
4. O2 Sats
5. Consciousness/communication (awake/rousable/no response)
6. Circulation (BP - full VS generally assessed)
7. Activity (moving extremities) - risk for falls