sedatives Flashcards
Sedation
state of ↓ irritability & excitement, usually characterized by drowsiness
Sedatives
High doses can cause a profound depression of the CNS that resembles anesthesia
Normal doses –> mild CNS depression, animal conscious but calm
- can be a pre-anesthetic drug
Alpha 2 agonists
Sedative analgesic & skeletal muscle relaxant • ↓ anxiety • provide chemical restraint • provide some analgesia ** Rapidly reversible!!
MOA of Alpha2 agonists
Bind Alpha2 receptors –> ↓ NE & dopamine release in CNS & peripheral NS
what effects does alpha 2 agonists have?
- MODULATE PAIN
- control BP, HR
- sedation
Side effects
• ↓ CO
Xylazine
Sedative & muscle relaxation
• Transient analgesic effects – none for extremities
Side effects of Xylazine
• Emesis -- pre-tx w/ atropine • Severe bradycardia --> ↓ CO • prolonged vasodilation • Massive ↑ in urine production (2hr) - do urethral obstruction Sx fast!!
what are the reversal agents for xylazine?
Dog - Yohimbine
Horse/ ruminant: Tolazoline
Medetomidine
+ reversal agent
> sedation (compared to xylazine) & good analgesia
• reversed w/ Atipamezole
Dexmedetodimine
• Sedation ceiling
• Poor analgesia
• Do NOT use Atropine for bradycardia
–> hypertension!
Alpha2 antagonists
• Yohimbine / tolazoline
- for xylazine
- Side effects
• hypotension –> death
• Atipamezole
- for medetomidine & detomidine
Benzodiazepines
CONTROLLED SUBSTANCE
• Mild tranquilizing effect , Poor sedation
• facilitates GABA binding –> Cl enter –> hyperpolarization of neurons
Drugs
• diazepam
• Midazolam – Main use = seizure tx
• zolazepam
Benzodiasepine reversal
Flumazenil
• in birds
• expensive