DRUGS

Question 1

Direct Acting Parasympathomimetics

Answer 1

Ach- rapid hydrolysis, non-specific, not used
Methacholine- muscarinic-specific, less hydrolyzed, test for bronchoconstriction
Bethanecol- muscarinic-specific, hydrolysis-resistant, used to treat bowel tone, urinary retention
Pilocarpine- tertiary amine, not hydrolyzable, treat Glaucoma and Sjogrens
Cevimeline- better treatment for Sjogrens

Question 2

Contraindications for Direct Acting Parasympathomimetics

Answer 2

no IM, IV, asthmatics, hyperthyroid, peptic ulcers, intestinal bladder obstructions

Question 3

Indirect-acting anticholinesterases

Answer 3

Reversible
Physostigmine- tertiary, glaucoma, antidote
Neostigmine- quaternary, MG, reverse non-depolarizing block, glaucoma, urinary retention, and most importantly GI stasis
Pyridostigmine- slow release, MG
Edrophonium- rapid onset and early termination, test for MG

Question 4

Indirect- acting anitcholinesterases

Irreversible

Answer 4

DFP- nerve gas, physostigmine
Sarin
Parathion- agricultural insectide
Malathion- slightly better insectide

Question 5

Selective alpha 1 receptor agonists

Answer 5

Phenylephrine-COMT resistant, little effect on myocardium, pupillary dilation, nasal congestants
Imidazoline- COMT, MAO resistant
Oxymetazoline, xylometazoline- related drugs
Midodrine- prodrug, increases blood pressure, treats orthostatic hypotension

Question 6

Selective alpha 2 agonists

Answer 6

Clonidine- imidazoline, stimulate central and postsynpatic alpha 2 receptors (overdose causing vasoconstriction). Decreases cardiac output, decreases TPR
Guanfacine- more selective for alpha 2 receptors
Alpha methyl dopa- more selective for alpha 2 receptors

Question 7

Selective beta 2 agonists (all resistant to COMT metabolism)

Answer 7

Albuterol- most selelctive, rescue inhaler
Terbutaline- paretneral use, successful bronchodilator, uterine relaxation
Ritodrine- prevent/delay premature labor
Salmeterol- selective, long-lasting inhlaer
Formoterol- long, but faster-acting than salmeterol

Question 8

Selective beta 1 agonist

Answer 8

Dobutamine- increases cardiac output by increasing contractility, treat CGF/cardiogenic shock

Question 9

Indirect-acting sympathomimetic amines

Answer 9

Tyramine- enters via uptake 1 to displace NE, understand 3 situations
Amphetamines

Question 10

Mixed-acting sympathomimetics (both indirect+direct)

Answer 10

Ephedrine- resistant to MAO/COMT, can be used orally, anti-asthma, nasal decongestant
Pseudoephedrine= sudafed
Abuse- hypertension, vasoconstriction=stroke, convulsions

Question 11

Alpha receptor blockers (non-specific)

Answer 11

Phenoxybenzmine- irreversible blockade, decrease blood pressure, management of pheochromocytoma
Phentolamine- short acting, competitive, treat hypertensive crises caused by tyramine

Question 12

Alpha 1 receptor blocker

Answer 12

Prazosin- decreased blood pressure with reflexive tachcardia, benign prostate hypertrophy
Tamsulosin, Alfuzosin, Silodosin- can’t ejaculate

Question 13

Alpha 2 receptor blocker

Answer 13

Yohimbine- aphrodisiac, most selective alpha 2 antagonist

Question 14

PDE5 inhibitor (for sexual dysfunction)

Answer 14

Sildenafil (and other afils)

Question 15

Beta blockers (non-specific)

Answer 15

Propanolol- decrease HR, decrease cardiac output, used for antiarrhythmic, pheochromocytoma
Contraindications- asthmmatic
Timolol- inhibits aqueous humor secretion, 1st line treatment of glaucoma

Question 16

Beta 1 receptor blocker (spare bronchioles)

Answer 16

Metoprolol- Propanolol
Atenolol
Betaxolol- glaucoma
Esmolol- short duration

Question 17

Mixed alpha and beta blockers

Answer 17

Labetalol- pheochromocytoma, hypertension crises during pregnancy
Carvedilol- treat heart failure (increase cardiac output)

Question 18

Mg and all other impermeant polyvalent cations

Answer 18

Compete with Ca++ at an external site that allows Ca++ entry and reduce neurally evoked ACh release

Question 19

Aminogycoside antibiotics (-mycin)

Answer 19

Reduce evoked ACh release by reducing of Ca++ entry through Ca++ channels

Question 20

Latrotoxin (black widow spider venom)

Answer 20

causes a huge asynchronous barrage of vesicular exocyotsis and MEPPs

Question 21

Latanoprost

Answer 21

prostaglandin agonist increases AH outflow, irreversible darkening of iris, and longer eyelashes

Question 22

Muscarinic Blockers

Answer 22

Atropine- mydriasis, cyloplegia, COPD (ipratropium tiotropium), treat parkinson’s, increase heart rate during spinal anesthesia, decrease secretions
Homoatropine- used for ciliary spasm
Cyclopentolate, tropicamide- mydriasis