CNS Depressants

Question 1

Barbiturates

Answer 1

• Schedule II, III, IV
• Long-acting schedule IV = phenobarbital
• MOA: GABA stimulation
• Indication: anti-epileptic, sedative, hypnotic
• NO REVERSAL AGENT (usually replaced by benzos)
• Narrow therapeutic window; easy to overdose
• Side effects: respiratory depression, bradycardia, ataxia, dependence & tolerance, REM rebound (vivid dreams & nightmares), hangover effect, skin eruption, constipation, paradoxical effects (anxiety)
• Decreases the effects of oral contraceptives
• Contraindications: pregnancy & with use of other sedative-hypnotics (alcohol, opioids)

Question 2

Benzodiazepines (-lam, -pam)

Answer 2

• Schedule IV
• Ex: lorazepam, diazepam, chlordiazepoxide (for ETOH withdrawal), midazolam (brand name versed; pre-op)
• MOA: GABA stimulation
• PO, IV, IM
• Indications: sedative (anxiolytic; prevents ETOH withdrawal symptoms), epilepsy (anti epileptic), spasms (muscle relaxant), insomnia (hypnotic), anesthesia induction (sedative/hypnotic)
• Much less risk of dependence

Question 3

Flumazenil

Answer 3

• Benzos reversal agent

Question 4

Zolpidem

Answer 4

• Nonbenzo hypnotic; schedule IV
• MOA: GABA enhancer
• PO & SL
• Indication: short-term use (<10 days) only PRN for insomnia
• Side effects: hypotension, hangover effect (daytime sleepiness, HA), lightheadedness, fall
• Contraindications: sleep-apnea, chronic respiratory disorders, children, pregnancy, breastfeeding, concurrent use with other CNS depressants
• Duration of action lasts for 8 hours so do not give late at night

“Falling head hits light switch”

Question 5

Inhalation Anesthetics

Answer 5

• General anesthesia
• Ex: Nitrous Oxide (NO), Isoflurane (liquid)
• Fast induction & fast reversal/recovery
• Eliminated by ventilation
  - Reversal agent: deep breathing & intubation/ventilation
• Adverse effects: anesthesia awareness, overdose (respiratory depression, hypotension, brady-dysrhythmia), HA, confusion, N/V, shivering/chills, malignant hyperthermia (watch for liver failure)

“Anesthetics are only helpful cuz Nadia & Vlad studied carefully, making headway”

Question 6

Dantrolene

Answer 6

• IV to treat malignant hyperthermia

- Monitor for liver failure

Question 7

IV Anesthetics

Answer 7

• General anesthesia
• Rapid onset & short duration of action
• Ex:
  - Etomidate: seen in ER when intubating
  - Propofol: high risk of infection, use vial within 6hrs
  - Contraindications: allergy to egg & soy bean
  - Ketamine: side effects = paradoxical effect
  - Can cause hallucinations, delirium & confusion
  - Benzos (midazolam)
  - Opioids: morphine & fentanyl; naloxone to reverse
  - Neuromuscular blockers: succinylcholine & vecuronium
  - Sucx has no reversal

Question 8

Neostigmine

Answer 8

• Reversal agent for vecuronium

- Used in treatment for MG

Question 9

Regional Anesthetic

Answer 9

• Caines
• Anesthetic agent injected around nerves
• No LOC
• MOA: prevent conduction of nerve impulses at injection site (motor, sensory, autonomic)
• Na Channel blockers
  - Procaine
  - Lidocaine

Question 10

Succinylcholine

Answer 10

• Depolarizing paralytic agent
• MOA: ACh agonist; binds to nicotinic receptor at the NMJ
  - Causes sustained depolarization —> muscle paralysis
• No reversal agent —> incubate/ventilate until drug is metabolized
• Side effects: hyperkalemia
• Adverse effects: respiratory depression, apnea, malignant hyperthermia
• Contraindication: pregnancy, MG
• Does not cross BBB —> not CNS effects

Question 11

Vecuronium & Pancuronium

Answer 11

• Non-depolarizing paralytic agent
• MOA: competitive antagonist (binds to ACh receptors) —> paralysis
• Side effects: histamine release —> rash, hives, angioedema, bronchospasm, low BP, tachycardia
• Nursing: antihistamine to treat, need to use reversal agent (neostigmine)

Vector —> Bee —> Sting —> histamine release

Question 12

Cyclobenzapine & Carisoprodol

Answer 12

• Centrally acting muscle relaxants
• Side effects: sleepiness, lightheadedness, fatigue, fall & physical dependence
• Nursing: educate on safety (avoid CNS stimulants/depressants & driving), taper the dose & avoid stopping abruptly

Question 13

Interferon Beta 1a & 1b

Answer 13

• For MS
• Interferon beta 1a: IM/SubQ
• Interferon beta 1b: SubQ
• Side effects: flu-like symptoms, myalgia, arthralgia, muscle spasms, depression, suicidal ideation, dizziness, fatigue
• MS exacerbation —> use prednisone

“Fuck Me All My Dogs Smell Disgusting Forreal”