Pharmacology II: Sedatives & Induction Agents

Question 1

Phenothiazine
Drug: Acepromazine
Action: (2)
Possible side-effects: (6)

Answer 1

1. Action:
   - Tranquilizer –> sedation, antiemetic
   - No analgesia!
2. Side effects:
   - Hypotension/hypothermia
   - Prominent nictitans membrane
   - Prolonged sedation (6-8hrs)
   - Penile prolapse
   - Idiosyncratic aggression
   - Increased risk for seizures historically reported (not confirm w/follow up studies)

Question 2

Common sedatives used before surgery (4)

Answer 2

1. Phenothiazines
2. Benzodiazepines
3. Alpha2 agonists
4. Opiates

Question 3

Phenothiazines should not be given to patients… (7)

Answer 3

With…
1. Epilepsy or Hx of seizures
2. Liver disease
3. Heart disease
Who are…
4. Geriatric or pediatric
5. In dehydration/hypotension/shock
6. Breeding stallions (penile prolapse)
7. Receiving eye exams

Question 4

Benzodiazepines
The drugs (4)
Action (3)

Answer 4

1. Drugs:
   - Diazepam (valium)
   - Midazolam (versed)
   - Alprazolam (xanax)
   - Zolazepam (part of telazol)
2. Action:
   - Tranquilizer
   - Muscle relaxant
   - Antiseizure by enhancing GABA effects in brain

Question 5

Benzodiazepines
Advantages: (4)
Possible side effects: (4)

Answer 5

1. Advantages:
   - Reversal agent (flumazenil)
   - Min depression of resp or cardio systems
   - Short-acting (20min)
   - Can be combined with ketamine or tiletamine
2. Side effects:
   - Appetite stim
   - Liver failure if given orally to felines
   - Hypotension if IV inj too rapid
   - Diazepam is painful & not well absorbed if given IM

Question 6

Alpha2 Agonistis
The drugs: (3)
Actions: (2)

Answer 6

1. Drugs:
   - Xylazine (rompun)
   - Dexmedetomidine (dexdomitor)
   - Medetromidine (domitor)
2. Action:
   - Sedative that decreases norepinephrine release (inhibits sympathetic nerve system)
   - Analgesia (shorter than sedation)

Question 7

Alpha2 Agonist
1. Possible side effects: (5)
2. Reversal agent: (2)

Answer 7

1. Side effects:
   - Profound bradycardia; AV heart block
   - Maintains BP thru vasoconstriction
   - Vomiting (esp cats)
   - Risk of bloat in deep chested dogs
   - Cattle very sensitive
2. Reversal:
   - Yohimbine
   - Atipamezole

Question 8

T/F: Use of Alpha2 Agonist is mostly limited to healthy, young dogs & horses being closely monitored

Answer 8

True

Question 9

Opioids
The drugs: (7+)
Action: (1)

Answer 9

1. Drugs:
   - Butorphanol
   - Morphine
   - Buprenorphine
   - Hydromorphone
   - Oxymorphone
   - Hydrocodone
   - Codeine
   - Etc
2. Action
   - Sedation & analgesia by binding to opiate receptors of CNS

Question 10

Opioids
Possible side effects: (5)
Reversal agent: (1)

Answer 10

1. Side effects:
   - Resp depression
   - Excitement if given rapidly IV
   - Excitement if used alone in cats or horses
   - Vomiting
   - Impaired thermoregulation
2. Reversal
   - Naloxone (narcan)

Question 11

Induction Agents are drugs used to…
They are sometimes used alone for…

Answer 11

1. Facilitate smooth & rapid transition from consciousness to unconsciousness
2. Short anesthetic procedures

Question 12

Injectable vs Mask Down
FYI: Quiz question!!

Answer 12

Question 13

Induction agents (5)

Answer 13

1. Alfaxalone
2. Propofol
3. Barbiturates
4. Dissociative agents (ex keta)
5. Guaifenesin

Question 14

Alfaxalone (Alfaxan)
Actions: (3)
Advantages: (3)

Answer 14

1. Actions:
   - Neuroactive steroid: anesthesia by GABA enhancement
   - IV inj should be administered slowly over 60sec
   - Short acting anesthetic for both procedures & induction (IV & IM)
2. Advantages:
   - Metabolized rapidly by liver
   - Cardiovascular sparing: heart safe
   - Safe to use as a continuous rate infusion