Adrenergic/Cholinergic Drugs

Question 1

alpha 2 agonists are good for ????? bad for????

Answer 1

good for premeds, anesthesia, standing procedures
bad for patients with compromised CV function

Question 2

reducing the dose of an alpha 2 agonist will do what?

Answer 2

dcrease the duration but not the magnitude of the effects

Question 3

how do alpha 2 agonists: provide sedation and analgesia, and reduce cardiac output?

Answer 3

sedation: inhibition of norepinepherine release in the brainstem
anelgesia: decreased neurotransmitter release and signal transmission is afferent pathways
cardiac output: initial effect is vasoconstriction, then relfex bardycardia, presynaptic effect leading to vasodilation

Question 4

describe the drug type, use, side effects of: Xyalzine

Answer 4

drug type: alpha 2 agonist
use: sedative in large animal
side effects: AV block, reduced GI motility, sweating, increased myometrial tone, makes cats vomit

Question 5

describe the drug type, use, side effects of: Detomidine

Answer 5

drug type: alpha 2 agonist
use: sedation and pain for standing sx in horses mostly, sometimes cattle
side effects: WAY more potent than xyalzine, less likely to cause premature delivery than xylazine

Question 6

describe the drug type, use, side effects of: Dexmedetomidine

Answer 6

drug type: alpha 2 agonist
use: sedation/premed for small animals
side effects: makes 50% of cats vomit

Question 7

how is dexmedetomidine different from medetomidine?

Answer 7

dex is a pure active enamtiomer while med is both enantiomers and it is therefore half as potent

Question 8

alpha 2 agonists have better anelgesia and sedation when you

Answer 8

pair it with an opiod

Question 9

describe the drug type, use, side effects of: dobutamine

Answer 9

drug type: beta 1 agonist
use: positive ionotrope, DOES NOT increase heart rate, short half life so given as a CRI
side effects: tachycardia in high doses, seizures in cats

Question 10

describe the drug type, use, side effects of: clenbuterol

Answer 10

drug type: beta 2 agonist
use: bronchodilator, sometimes treat equine asthma, inhibits uterine contractions
side effects: can be used as a growth promoter and is banned in food animals

Question 11

describe the drug type, use, side effects of: epinephrine

Answer 11

drug type: non selective adrenergic agonist
use: treatment of anaphylaxsis (vasoconstriction but dilation of airways, increases cardiac output)
side effects: increases myocardial oxygen consumption

Question 12

describe the drug type, use, side effects of: prazosin

Answer 12

type: alpha 1 antagonist
use: aterial and venous vasodilator, used to treat urinary blocks in cats
side effects: very protein bound

Question 13

describe the drug type, use, side effects of: Atipamezole

Answer 13

type: alpha 2 antagonist
use: compeitive alpha 2 antagonist,reverses sedation and anelgesia
side effects: reverses everything!

Question 14

describe the drug type, use, side effects of: atenolol

Answer 14

type: beta 1 antagonist
use: negative ionotrope, treat ventricular tachycardia and arterial hypertension, sometimes used in kidney disease high BP

Question 15

describe the drug type, use, side effects of: Neostigmine

Answer 15

type: cholinergic
use: reversible inhibitor of acetylcholinerase, increases gut motility, treat myasthenia gravis

Question 16

describe the drug type, use, side effects of: atropine and glycopyrrolate
which more easily crosses the BBB?

Answer 16

type: anticholinergics
use: competitive muscarinic antagonists to reduce response to PS nerve impulses
adverse effects: tachyarrythmias, mania, ileus in horses
glycopyrrolate is more polar than atropine so it doesn’t easily cross the BBB so it has less CNS side effects associated with it

Question 17

describe the drug type, use, side effects of: hyoscine butylbromide

Answer 17

type: anticholinergic
use: similar effects to atropine, useful in horses with gas colic, acute asthsma treatment, rectal exams in horses (remember, this will decrease gut motility!)