Drugs Flashcards
(31 cards)
1
Q
Bethanechol
A
- direct acting parasympathomimetic
- muscarinic agonist
- oral medication
- increase bladder contractility
- increase GI motility
- do not use if GI obstruction
2
Q
Neostigmine
A
- indirect acting parasympathomimetic
- treatment of rumen atony
- stimulating GI motility, bladder emptying
- treatment of myasthenia gravis
- contraindicated: peritonitis, GI obstruction, pregnancy, other cholinesterase inhibitors
3
Q
Pyridostigmine
A
- indirect acting parasympathomimetic
- onset 1 hour, lasts 8-12 hours
- treatment for myasthenia gravis
4
Q
Edrophonium
A
- indirect acting parasympathomimetic
- injectable
- onset 1 minute, lasts 10 minutes
- tensilon test for myasthenia gravis
5
Q
What are the effects of Atropine?
A
- tachycardia
- mydriasis
- reduces salivation
- slows gut
- bronchodilation
- difficulty with urination
6
Q
Atropine Sulfate
A
- direct acting parasympatholytic
- treats bradyarrhythmias/bradycardia, toxicity, and cholinergic crisis/anticholinesterase overdose
- should not be used if tachycardia present
7
Q
Glycopyrrolate
A
- direct acting parasympatholytic
- slower onset and longer duration than atropine
- treats same as atropine (bradycardia)
- pre-med in anesthesia
8
Q
Oxybutynin and Propantheline
A
- direct acting parasympatholytics
- relaxes detrusor muscle and allows bladder to better fill
9
Q
Catecholamines
A
- direct acting sympathomimetic a/b agonists
- poorly absorbed after oral administration, usually given by injection
- readily absorbed from respiratory tract
- do not readily cross BBB
10
Q
Catecholamines negative effects
A
- can predispose to arrhythmias/tachycardia
- anxiety, restlessness, tremors
- cerebral hemorrhage
- altered perfusion of kidneys
- extravasation of NE/dopamine can cause tissue damage
11
Q
Epinephrine
A
- catecholamine
- activates all adrenergic receptors
- B1: cardiac contraction, B2: bronchodilation and vasodilation, A1: vasoconstriction
- no PO administration
- used for cardiac arrest, anaphylaxis/anaphylactoid reaction
- used with local anesthetics to produce local vasoconstriction and delay absorption
12
Q
Norepinephrine
A
- catecholamine
- activates A1, A2, B1, but not B2
- vasoconstriction, stronger at similar doses to epinephrine
- increases afterload
13
Q
Dopamine
A
- catecholamine
- low dose: dopamine agonist
- medium-low dose: B1 agonist
- medium-high dose: B1 agonist
- high dose: A1 agonist
- very short half life
14
Q
Dobutamine
A
- sympathomimetic, direct acting, synthetic catecholamine B1 agonist
- IV administration
- positive inotropic effect
- used for acute heart failure
15
Q
Isoproterenol
A
- sympathomimetic, direct acting, synthetic catecholamine, nonspecific B agonist
- IV administration
- positive inotropic effect
- bronchodilation
16
Q
Phenylephrine
A
- sympathomimetic direct acting alpha 1 agonist
- increases peripheral vascular resistance
- effects immediately, lasts 20 minutes
- used to treat hypotension in dogs and cats
17
Q
Ractopamine and Zilpaterol
A
- sympathomimetic, direct acting non-selective beta agonist
- particularly beta 3
- partitioning agents
- increase weight gain rate, feed efficiency and carcass leanness
18
Q
Use and cautions of selective beta-2 agonists
A
- bronchodilators in treatment of asthma/COPD
- cilia augmentors
cautions: avoid in patients with cardiovascular disease
19
Q
Albuterol
A
- sympathomimetic direct acting selective beta 2 agonist
- often used with inhalers
20
Q
Clenbuterol
A
- sympathomimetic direct acting selective beta 2 agonist
- oral syrup used in equines
21
Q
Tetrabutaline
A
- sympathomimetic direct acting selective beta 2 agonist
- tablet or injectable in small animals
22
Q
General use of indirect/mixed acting sympathomimetics
A
- use for CNS effects
- behavior modification (antidepressants)
23
Q
Phenylpropanolamine
A
- sympathomimetic mixed acting
- indirect increase in NE in bladder, and direct alpha 1 agonist
- used in small animals to treat urinary incontinence due to urethral sphincter hypotonus
24
Q
Ephedrine
A
- sympathomimetic mixed acting
- indirect increase in NE release and direct alpha 1 and beta activation
- used as CRI to maintain blood pressure under anesthesia
25
Phenoxybenzamine
- sympatholytic direct acting, non-specific alpha antagonist
- binds irreversibly to receptors
- available as oral capsule
- treats urinary retention due to urethral hypertonicity, and pheochromocytoma
- relaxes internal sphincter
- in small animals
26
Prazosin
- sympatholytic direct acting, alpha 1 antagonist
- urinary smooth muscle relaxation, vasodilation
- used in small animals to treat urinary retention due to urethral hypertonicity
27
Propranolol
- sympatholytic direct acting, non-specific beta antagonist
- decreases SA firing (bradycardia) and AV conduction
- decreases cardiac output and myocardial oxygen demand
- increases airway resistance
- used to treat supraventricular tachyarrhythmias, feline hyperthyroidism, and methylxanthine toxicosis
- oral or injectible
- crosses BBB, significant first-pass effect
28
Propranolol Cautions
- bradycardia, hypotension, bronchospasm
- receptor desensitization and upregulation
- contraindicated with heart failure, sinus bradycardia, heart block, and bronchospastic lung disease
- caution if hepatic or renal disease, hypoglycemia, or digitalis
29
Atenolol
- sympatholytic direct acting, beta 1 antagonist
- longer half-life than propranolol
- lack of beta-2 effects, so better choice for patients with bronchoconstriction
30
Esmolol
- sympatholytic direct acting, beta 1 antagonist
- ultra short acting
- used IV for controlling arrhythmias
31
Reserpine
- sympatholytic indirect acting
- blocks NE uptake into vesicles which reduces storage of NE and leads to mediator depletion
- used for calming equines
