Drugs For Pharmacotherapy Exam 2

Front 1

Reversible alpha receptor antagonists

Back 1

Phentolamine, Prazosin, Labetalol

Front 2

Phenoxybenzamine

Back 2

Agent related to nitrogen mustards--forms a reactive ethyleneimonium intermediate that covalently binds to alpha receptors--irreversibly

Front 3

Alpha receptor antagonist drugs--Cardiovascular effects

Back 3

- Cause a lowering of peripheral vascular resistance and blood pressure
- Can PREVENT the pressor effects of usual doses of alpha agonists
- May cause postural hypotension and reflex tachycardia

Front 4

Alpha receptor antagonist drugs--Bladder and Prostate

Back 4

Decreases resistance to flow of urine

Front 5

Phentolamine (imidazoline derivative)

Back 5

Potent competitive antagonist @ both alpha1 and alpha2 receptors; Causes a reduction in peripheral resistance through blockade of a1 receptors and a2 receptors on vascular smooth muscle;
Increased cardiac stimulation induced by phentolamine; increased NE release from symp nerves
MAJOR USE in management of pheochromocytoma (tumor found in adrenal medulla that releases a mixture of EPI and NE)

Front 6

Phenoxybenzamine

Back 6

Binds covalently to alpha receptors, causing irreversible blockade of long duration;
Inhibits reuptake of NE and blocks H1, ACh, and serotonin receptors; Adverse effects include postural hypotension and tachycardia;
MAJOR USE in TX of Pheochromocytoma (tumor of adrenal medulla releasing EPI and NE);
Also for Tx of shock

Front 7

Prazosin (Sympatholytics)

Back 7

Management of HTN; highly selective for a1 receptors and low affinity for a2, explaining relative absense of tachycardia compared to phenoxybenzamine and phentolamine; relaxation of both arterial and vascular smooth muscle;
Extensively metabolized--50% bioavailability after admin

Front 8

Terozosin

Back 8

reversible a1-selective antagonist effective for HTN;
approved for symptoms of BPH

Front 9

Tamsulosin

Back 9

Competitive a1 antagonist with structure different from other a1 receptor blockers;

Front 10

Labetalol and Carvedilol

Back 10

Has both a1-selective and B-antagonistic effects;
Causes decrease in peripheral vascular resistance and orthostatic hypotension

Front 11

Propranolol

Back 11

Standard of Beta receptor antagonist; Low bioavailability due to major first-pass metabolism; Large volume of distribution due to lipophilicity--therefore can cross BBB;

Front 12

Esmolol

Back 12

Beta receptor antagonist; ultra-short-acting B1-selective adrenergic antagonist; structure contains ester linkage and steady-state achieved quickly;

Front 13

Beta receptor antagonist drugs--Effects on Cardiovascular System

Back 13

Lowers BP in patients with HTN; effects on heart and blood vessels; suppression of renin-angiotensin system; conventional doses DO NOT cause hypotension in normal pts.

Front 14

Beta receptor antagonist drugs--Effects on Respiratory Tract

Back 14

Blockade of the B2 receptors in bronchial smooth muscle may lead to increase airway resistance; avoid in pts with asthma

Front 15

Beta receptor antagonist drugs--Effects on the Eye

Back 15

Several B-blocking agents reduce intraocular pressure; tx of glaucoma; decreased aqueous humor production

Front 16

Pindolol

Back 16

PARTIAL B-receptor AGONIST activity

Front 17

Metoprolol and Atenolol

Back 17

B1-selective antagonism; May be safer in patients who have experienced bronchoconstriction in response to propranolol;

Front 18

Role of Beta-receptor blocking drugs in Ischemic Heart Disease

Back 18

Beta-adrenoceptor blockers reduce frequency of anginal episodes and improve exercise tolerance in pts with angina; related to blockade of cardiac beta receptors, thus decreasing cardiac work and reduction in oxygen demand;

Front 19

Role of Beta-receptor blocking drugs in HTN

Back 19

Proved to be effective and well-tolerated; often used with either a diuretic or vasodilator; despite short half-life, drug can be administered once or twice daily

Front 20

Pilocarpine (Cholinomimetic)

Back 20

Naturally occuring M-Selective; miotic and for tx of XEROSTOMIA associated with Sjogren's syndrome

Front 21

Neostigmine and Physostigmine (Cholinomimetic)

Back 21

Pseudoirreversible Acetylcholinesterase inhibitors

Front 22

Organophosphates (Cholinomimetic)

Back 22

IRREVERSIBLE Acetylcholinesterase inhibitors

Front 23

Atropine (Parasympatholytic)

Back 23

Muscarinic receptor antagonist;
TERTIARY AMINE;
Block of M2 receptors leaves SNS unopposed; In eye, results in mydriasis (dilation of pupil); reduces GI activity as an antispasmodic; At low dose, decrease HR and at high dose, M2 receptors on SA node are blocked resulting in modest increase;
blocks salivary glands producing drying effect on oral mucus membrane and blocks sweat glands

Front 24

Solifenacin (Parasympatholytic)

Back 24

M3 selective; Tx of overactive bladder

Front 25

Tiotropium (Parasympatholytic)

Back 25

Approved for COPD; Kinetic selectivity for M1 and M3 receptors--prolonged duration; BLOCK of M2 receptors is undesirable with respect to Tx of airway constriction

Front 26

Tolterodine (Parasympatholytic)

Back 26

Used for incontinence, TX of overactive bladder

Front 27

Muscarinic receptor characteristics

Back 27

G-protein coupled type; agonist binding activates the IP3 and DAG cascade; DAG opens smooth muscle Ca2+ channels and IP3 releases Ca2+ from ER stores.

Front 28

Muscarinic effects in the Eye

Back 28

Contraction of Sphincter muscle of iris (miosis) and contraction of ciliary muscle resulting in accommodation (near vision)

Front 29

Muscarinic effects in the Heart

Back 29

SA node to decrease rate; Atria to decrease contractile strength; AV Node to decrease conduction velocity; Ventricles to decrease contractile strength

Front 30

Muscarnic effects in the Blood vessels

Back 30

Arteries and veins dilate; constrict in HIGH DOSE direct effect

Front 31

Muscarnic effects in the Lung

Back 31

Bronchoconstriction in bronchial muscle and stimulation of bronchial glands

Front 32

Muscarinic effects in GI Tract

Back 32

Increase motility, relaxation of sphincters, and stimulation of secretion

Front 33

Muscarnic effects on Urinary Bladder

Back 33

Contraction of Detrusor muscle, relaxation of Trigone and sphincter

Front 34

Muscarinic effects on Glands

Back 34

Secretion of sweat, salivary, lacrimal, and nasopharyngeal

Front 35

Nicotine

Back 35

Nicotine Agonist @ Ganglionic receptor; increases alertness, respiration, arterial pressure, skeletal muscle contractility, stimulates chemoreceptors;
HIGH Doses block Nn receptors

Front 36

Trimethaphan (Nicotinic Antagonist)

Back 36

Use IV for rapid decrease in BP (Emergency situations)

Front 37

Sympathomimetic Drugs

Back 37

Drugs that mimic the effects of NE and EPI; mediated by G-proteins on cell surface

Front 38

Indirect Sympathomimetic agents act by these two mechanisms:

Back 38

(1) Displacement of stored catecholamines from the adrenergic nerve ending (amphetamine and tyramine) and (2) inhibition of reuptake of catecholamines already released (cocaine and tricyclic antidepressants)

Front 39

Beta adrenoceptors

Back 39

B1 receptors have approximately equal affinities for EPI and NE, whereas B2 receptors have higher affinity for EPI than for NE

Front 40

Alpha1 Adrenoceptors

Back 40

Alpha1 receptor stimulation leads to formation of IP3 and DAG by G-protein activation of PLC; DAG then activates PKC and IP3 increases [Ca2+];

Front 41

Alpha2 Adrenoceptors

Back 41

Inhibit adenylate cyclase and thus causing decrease in cAMP levels.

Front 42

Sympathomimetic Drugs

Back 42

Drugs that mimic the effects of NE and EPI; mediated by G-proteins on cell surface

Front 43

Indirect Sympathomimetic agents act by these two mechanisms:

Back 43

(1) Displacement of stored catecholamines from the adrenergic nerve ending (amphetamine and tyramine) and (2) inhibition of reuptake of catecholamines already released (cocaine and tricyclic antidepressants)

Front 44

Beta adrenoceptors

Back 44

B1 receptors have approximately equal affinities for EPI and NE, whereas B2 receptors have higher affinity for EPI than for NE;
activation results in increase adenylate cyclase activity and thus increase conversion of ATP to cAMP, an important secondary messenger

Front 45

Alpha1 Adrenoceptors

Back 45

Alpha1 receptor stimulation leads to formation of IP3 and DAG by G-protein activation of PLC; DAG then activates PKC and IP3 increases [Ca2+];

Front 46

Alpha2 Adrenoceptors

Back 46

Inhibit adenylate cyclase and thus causing decrease in cAMP levels.

Front 47

Beta receptor activation in Heart

Back 47

Increases influx of Ca2+ across the cell membrane

Front 48

Beta receptor activation in smooth muscle

Back 48

Promotes relaxation of smooth muscle

Front 49

Dopamine receptor activation

Back 49

D1 activation causes stimulation of Adenylate cyclase; smooth muscle relaxation;
D2 activation causes inhibition of adenylate cyclase activity, opening K+ channels and decreasing calcium influx.

Front 50

Epinephrine (Endogenous Sympathomimetic Catecholamine)

Back 50

Potent vasoconstrictor and cardiac stimulant; B1 receptors in heart and alpha receptors in vascular beds; Also activates B2 receptors in some vessels, leading to vasodilation and increased blood flow to skeletal muscle;

Front 51

Norepinephrine (Endogenous Sympathomimetic Catecholamine)

Back 51

Same as EPI, but little effect on B2. Consequently, NE increases Peripheral resistance and BP.

Front 52

Isoproterenol (Sympathomimetic)

Back 52

Very potent Beta receptor agonist and has little effect on alpha receptors. POTENT vasodilator--leading to marked increases in CO

Front 53

Fenoldopam (Dopamine agonist)

Back 53

D1 receptor agonist leading to peripheral vasodilation. IV for severe HTN;
to lower BP and preserve RBF

Front 54

Dobutamine (Sympathomimetic)

Back 54

Selective B1 synthetic catecholamine; ALSO activates alpha1 receptors.
Pressor; functionally cardioselective (Increase CO with minimal effect on TPR);
best example of B1 selective agonist

Front 55

Phenylephrine

Back 55

Pure alpha agonist; NOT a catechol and so is not inactivated by COMT, thus having much longer duration of oaction than catecholamines;
Effective mydriatic and decongestant and to raise BP

Front 56

Ephedrine and Pseudoephedrine

Back 56

Noncatechol, thus high bioavailability and long duration of action; activates Beta receptors; mild stimulant due to access to CNS;
Pseudoephedrine is its enantiomer

Front 57

Amphetamine

Back 57

CNS stimulant; readily enters CNS and effects mood, alertness, and decreased appetite;
Is a Phenylisopropylamine

Front 58

Tyramine

Back 58

By-product of tyrosine metabolism; Mechanism of action similar to NE; MAO inhibitors will intensify effects, leading to marked increases in BP; patients taking MAO inhibitors must avoid tyrosine containing foods.

Front 59

Cocaine

Back 59

peripheral sympathomimetic action resulting from inhibition of transmitter reuptake at noradrenergic synapes;
readily enters CNS and produces amphetamine-like effects that is shorter lasting and more intense; inhibits dopamine reuptake in CNS;
Potent vasoconstrictor due to buildup of NE in synaptic cleft

Front 60

Clonidine

Back 60

a2 agonist; decreases BP; acts on CNS inhibiting sympathetic vasomotor effects

Front 61

Metaraminol

Back 61

direct acting adrenergic agonist; Tx of shock--advantageous b/c does not decrease renal BF

Front 62

Albuterol

Back 62

Selective B2 agonist used as bronchodilator; Tx of chronic asthma; short acting with minimal cardiac stimulation; longer action compared to EPI

Front 63

Terbutaline

Back 63

short acting B2 agonist used as a bronchodilator; administered as metered-dose inhaler

Front 64

Salmeterol

Back 64

B2 selective agonist--LONG-acting bronchodilator

Front 65

Diazepam (Spasmolytic drug)

Back 65

Skeletal muscle relaxant; Acts at all GABAa synapses; used in patients with muscle spasms

Front 66

Baclofen (Spasmolytic)

Back 66

Skeletal muscle relaxant; reduces muscle spasms; GABAb mimetic; activation by baclofen on GABA results in hyperpolarization preventing release of excitatory NT; decreases Ca2+ influx, thus decreasing excitatory NT release; Analgesic in inhibiting release of Substance P; less sedative than Diazepam

Front 67

Tizanidine (Spasmolytic)

Back 67

Skeletal muscle relaxant; reduces muscle spasms via alpha 2 agonistic effects

Front 68

Dantrolene (Spasmolytic)

Back 68

Skeletal muscle relaxant; reduces muscle spasms; interferes with excitation-conduction coupling in muscle fibers;
INTERFERES with release of activator calcium trhough SR calcium channel by binding to Ryanodine receptor;
Tx of malignant hyperthermia

Front 69

Ryanodine receptor

Back 69

Channel where Ca2+ is released from the SR

Front 70

Botulinum Toxin (Spasmolytic)

Back 70

Skeletal muscle relaxant; reduces muscle spasms; local injection used to treat spastic disorders;
Stops release of ACh by removing amino acids necessary for ACh to fuse to membrane

Front 71

Succinylcholine

Back 71

Depolarizing agent; attaches to nicotinic receptors and acts like ACh to depolarize junction; constant stimulation of receptor;

Front 72

Reserpine

Back 72

Inhibits transport of Dopamine into storage vesicle during NE synthesis;
blocks vesicular NE and DA uptake, causing NE depletion;
CNS effects include increase vagal outflow and psychic depression

Front 73

Cyclobenzamine

Back 73

relieves acute muscle spasms caused by muscular strains or local tissue trauma; structurally related to tricyclic antidepressants and possesses antimuscarinic (atropine-like) effects and sedation;
ineffective in treating cerebral palsy or spinal cord injury; increases NE inhibitory influence on motoneurons (decreases NE uptake)

Front 74

Quinine (spasmolytic)

Back 74

Inhibits spread of muscle action potention;
Tx of muscle cramps

Front 75

Succinylcholine

Back 75

Agonist @ Nm receptors--acts at NMJ end plate; Phase I--oppens channel allowing for prolonged depolarization of end plate area, muscle fasciculations produces flacid paralysis (not reversible w/ ACh); Phase II--End plate area repolarizes, but is unresponsive to dep. stim., blockade can be reversed by ACH;
Use IV for paralysis of laryngeal and jaw muscles

Front 76

Tubocurarine (non-depolarizing blockade)

Back 76

Binds reversibly to Nm receptors for ACh at NMJ end-plate; causes flaccid paralysis, no preliminary contractions as in ScCh; IV only, does not get access to brain

Front 77

Mivacurium and Atracurium

Back 77

Alternatives to Tubocurarine; more rapid onset of action (3m); fewer liabilites than ScCh;

Front 78

Oxymetazolone (sympathomimetic)

Back 78

alpha2 agonist used to treat nasal decongestant;

Front 79

alpha methyl NE (levonordefrin), a sympathomimetic

Back 79

alpha2 agonist used to treat nasal decongestant; also acts on CNS to decrease BP

Front 80

Ritodrine (sympathomimetic)

Back 80

B2 agonist used to relax uterus and delay labor

Front 81

alpha methyl DOPA

Back 81

pro drug that is converted to alpha methyl NE

Front 82

Moxonidine (Sympathomimetic)

Back 82

I1 receptor (imidazole receptor), which may perpetuate the effects of morphine, so can use less of it)

Front 83

Bretylium (sympatholytic)

Back 83

Prevents NE release

Front 84

Guanethidine

Back 84

Chronic prevention of NE storage and acute prevention of NE release; initial sympathomimetic effect
chronic use causes NE depletion

Front 85

Bretylium (sympatholytic)

Back 85

Prevents NE release

Front 86

Guanethidine

Back 86

Chronic prevention of NE storage and acute prevention of NE release

Front 87

Bretylium (sympatholytic)

Back 87

Prevents NE release

Front 88

Guanethidine

Back 88

Chronic prevention of NE storage and acute prevention of NE release