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Pharmacotherapeutics I > Drugs > Flashcards

Flashcards in Drugs Deck (95):
1

Chloramphenicol

In neonates interferes with mitochondrial ribosomes and causes gray baby syndrome. Sx- poor feeding, decreased breathing, CV collapse, cyanosis, and death

2

Succinylcholine

short acting muscle relaxer used in surgery. Butyrylcholinesterase (BChE) hydrolysis of this creates a decreased rate of metabolism of succinylcholine resulting in prolonged paralysis after drug exposure.

3

N-acetyltransferase 2 (NAT2)

Catalyzes the acetylation (route of metabolism for specific drugs) of isoniazid, hydralazine, and procainamide. This does either slow or fast acetylators (slow=build up and fast = not working)

4

CYP2D6

Metabolizes metoprolol (lowers <3 rate), haloperidol (Antipsychotic), codeine, and fluoxetine (Depression)

5

Metoprolol

A beta blcoker used to decrease the heart rate. A poor metabolizer has potential toxicity with standard doses of this medication.

6

Codeine

Ineffective w/out metabolism by CYP2D6 to from the more potent opioid morphine. Normal codeine does not result in overdose.

7

Thiopurine S-Methyltransferase (TPMT)

Catalyzes the S-mehtylation of thiopurine drugs such as 6-mercaptopurine and azathiprine immunosuppressant agents (Used in CHEMO)

8

Zileuton

used for asthma by decreasing the airway inflammation by inhibitiing 5-lipoxygenase.

9

Warfarin

Metabolized predominately by CYP2C9. Warfarin's target is viamin K epoxide reductase (an enzyme that is required for vitamin K dependant generation of clotting factors)

10

Abacavir

HIV medication that has an idiosyncratic reaction with HLA-B*5701 by inducing hypersensitivity.

11

Aminoglycoside Antibiotics

Gentamicin, tobromycin, amikacin, neomycin, and streptomycin. Must be administered via a parenteral route due to poor GI absorption. Very water soluble w/ poor distribution into adipose tissue. Clearance is almost entirely renal

12

Vancomycin

Antibiotic.
Poorly absorbed orally although useful in tx of C.diff with PO route. Systemic infections require parenteral dosing.
Increases levels/effects of aminglycosides- used for infections together.
Half life of 5-11 hrs.

13

Phenytoin

Absorption from oral route is slow.
Highly protein bound
Consider diseases that result in decreased serum albumin concentration such at burns, nephrotic syndrome, and renal failure.
An example of a P450 inducer
Moves from 1st order quickly to zero order occurring even at therapeutic levels

14

Valproic acid

Used as antiepileptic and as a mood stablizer.
Bioavailability 90% relative to IV dose
Saturable protein binding 80-90% free fraction.
Metabolism extensively hepatic via glucuronidation (conjugation)
Only p450 inhibitor (in antiepileptic class.
Relationship b/w dose and total valproate [ ] is not linear.
Draw levels 2-4 days of initiation to etermine total valproic acid.

15

Carbamazepine

Anti-epileptic
Slow absorption
Highly protein bound to plasma albumin and alpha1-acid glycoprotein.
Concamitant tx w/ valproate sodium results in higher free fraction
Eliminated primarily by metabolic route, one active metabolite, carbamazepine 10, 11 epoxide.
Metabolized primarily by CYP3A4
Induces own metabolism and goes from a long 1/2 life to a shorter one.
Steady state= 2-5 days

16

Warfarin

Oral anticoagulant-rapid complete absoption.
Onset of action 24-72 hrs.
Peak effect 5-7 days
Highly protein bound (99%)
Metabolism primarily by CYP2C9

17

Digoxin

Cardiac medication
Absorbed by passive non-saturable diffusion in SI.
Distribution phase lasts 6-8 hrs.
Large volume to distribution. After distribuiton you have a 70:1 in the heart vs. in the blood.
Very narrow therapeutic index

18

Epinephrine

Andrenergic Agonist
Interacts with both alpha and beta
Low dose- mainly beta effects (vasodilation); high dose- alpha effects (vasoconstriction
CV: + inotropic, + chronotropic- increased CO
Alpha effects- vasoconstricts arterioles
B2- vasodilates vessels to liver and skeletal muscle
Net result- increased SBP w/ slight decrease in DBP
Respiratory- bronchodilation of smooth muscle (B2)
Hyperglycemia-decreased insulin release (alpha2) increased glycogenesis, increased release of glucagon (B2)
Lypolysis B1

19

Epinephrine therapeutic uses

Emergent tx of asthma, glaucoma, anaphylaxis, w/local anesthetics to prolong DOA through vasoconstriction

20

Epinephrine ADRs

CNS- anxiety, fear, tension, HA, tremor, hemorrahage, increased BP, cerebral hemorrhage
CV-arrhythmias
Pulmonary edema

21

Norepinephrine

Adrenergic Agonist
At therapeutic doses alpha 1 and beta 1 receptors are afected
CV- vasoconstriction in periphery (including kidney) reulting in elevated BP, baroreceptor reflex: increase BP -> increased vagal activity stimulation baroreceptors causing bradycardia.
Tx use shock through vascular resistance, increase BP

22

Dopamine

Adrenergic Agonist
Low doses act predominately on D1 receptors in renal, mesenteric, and coronary vascular beds (vasodilation).
Higher doses a positive inotrope (action at beta1)
High doses- vasoconstriction via alpha 1 receptors
DOC for shock, at appropriate doses is useful in management of low CO associated with compromised renal function such as in severe CHF.

23

Methoxamine

Adrenergic Agonist
Alpha 1 selective agonist
Not used often but used to tx shock

24

Phenylephrine

Adrenergic Agonist
Alpha 1 selective agonist
Used like psuedofedrin, Topical constrict vascular smooth muscle in relief or nasal congestion
Not catechol derivative so substrate for COMT
Induces reflex bradycardia when given parenterally, raises BP due to vasoconstriction.

25

Oxymetazoline

Adrenergic Agonist
Alpha 1 selective agonist
Topical, constrict vascular smooth muscle in relief of opthamic hyperemia.

26

Chlonidine

Adrenergic Agonist
Alpha 2 selective agonist
Lowers BP by suppressing sympathetic outflow
ADR dry mouth and sedation

27

a-methyldopa

Adrenergic Agonist
alpha 2 selective agonist
Metabolized to a-methylnorepinephrine which is an a agonist in CNS to decrease sympathetic outflow

28

Gaunfacine

Adrenergic Agonist
a-2 agonist in CNS to decrease sympathetic outflow
ADR dry mouth and sedation

29

Isoproterernol

Adrenergic Agonist
Nonspecific B agonist (acts at B1 and B2)
CV: + inotropic and chronotropic effects (B1); vasodilation of arterioles of skeletal muscle (B2)
Pulmonary- bronchodilation (B2)
Uses- stimulates heart in emergencies

30

Dobutamine

Adrenergic Agonist
B1 selective
Increases cardiac rate and output, usted to increased CO in CHF, racemic mixture cancers out alpha

31

Albuterol, pirbuterol, terbutaline

Adrenergic Agonist- B2 selective
Short acting bronchodilators (less cardiac stimulation)

32

Salmeterol and formoterol

Adrenergic Agonist
B2 selective agents
B2 long acting bronchodilator

33

Amphetamine

Indirect adrenergic agonist
CNS stimulant, increases BP by alpha effect of vasculature, beta effect on heart

34

Ephedrine

Mixed action
Alpha, beta, and CNS stimulant
Use- nasal sprays due to local vasoconstrictor activity; urinary incontinence
Long DOA

35

Phenoxybenzamine

Adrenergic antagonist Alpha blocker
Irreversible, nonselective and noncompetitive block, tx of pheochromocytoma to preclude HTN crisis that can result from manipulating tissue.

36

Phentolamine

Adrenergic antagonist Alpha blocker
Competitive, nonselective block (alpha 1 and 2 response is more E being created and alpha 1 decreased vasoconstriction)

37

Prazosin, doxazosin, terazosin

Adrenergic antagonist Alpha blocker
Selective alpha1 blocker- used for vasodilation
Tx- hypertension, BPH, CHF by relaxing the arterial and venous smooth muscle and decreased PVR.

38

Tamsulosin

Adrenergic antagonist Alpha blocker
Tx of BPH (benign prostate hyperplasia)
Inhibitor of Alpha 1 receptor on smooth muscle of prostate (decreases tone of bladder neck and prostate and improves urine flow.)

39

Propranolol (prototype)

Adrenergic antagonist beta blocker
Nonselective
Uses- lowers BP, used to tx angina, cardiac arrhythmias, MI, glaucoma, prophylaxis for migraines
Effects- lowers cardiac output (rate and force), prevents vasodilation, bronchoconstriction, increased Na retention, decreased glycogenolysis, and glucagon secretion

40

Timolol and nadolol

Adrenergic antagonist beta blocker
Nonspecific beta blocker
Uses- glaucoma and HTN

41

Acebutolol, atenolol, metoprolol, esmolol

Adrenergic antagonist beta blocker
Preferentially blocks beta 1 receptors- cardioselective
Eliminates unwanted bronchoconstriction, little effect of CHO- metabolims, or PVR
Useful in hypertensive DM pt on insulin or oral hypoglycemics

42

Pindolol and acebutal

Adenergic antagonists w/ partial activity
Weakly stimulate B1 and B2. Used for HTN

43

labetolol and carvediol

Antagonists of alpha1 and beta 1&2 receptors. Peripheral vasodilation, dont alter lipid of glucose levels. Carvediol decreased lipid peroxidation and vascular wall thickening to benefit CHF
Uses of labetolol- HTN, CHF, PIH, HTN emergenies -> rapidly lowers BP

44

Benzodiazepines

Midazolam, diazepam, alprozolam, chlorazepate, lorazepam, chlordiazepoxide, clonazepam, flurazepam, temazepam, triazolam, zolpidem
Do not activate receptor in absence of GABA. Still require 2 GABA to bind then benzo makes it work better
Highly selective, high affinity drugs that bind a single site on GABA receptor a1, a2, a3, or a5, and a y subunit.
Potency is correlated to hydrophobicity
Highly protein bound

45

Benzodiazepines

Admin via oral, transmucocal, IM and IV.
Metabolized by CYP3A4
Used as sleep enhancers, anxiolytics, sedatives, antiepileptics, muscle relaers, and for the tx of ETOH withdrawl.
ADRs related to therapeutic effects- amnesia
Antagonist Flumazenil reverses effects
High potential for development of tolerance, dependence, and addiction

46

Barbiturates

Butabarbital, butalbital, methohexital, pentobarbital, primidone, secobarbital, and thiopental.
Affect CNS sites in spinal cord, brainstem, and the brain.
Cause sedation, amnesia, and LOC by affecting GABA receptors,
Spinal cord- relaxes muscles and suppressed reflexes

47

Anesthetic barbiturates

Ionotrophic GABA receptor
Thiopental, pentobarbital, and methohexital
Act as agonists at GABA-a and enhance the receptors response to GABA (dont not require the presence of GABA at receptors)

48

Phenobarbital

Anticonvulsant Barbiturates
Less direct agonist. Works for inhibiiton effects but does not cause the same amount of sedation as anesthetics.

49

Barbiturates

Oral or IV admin.
Lipid solubility allows to enter CNS, termination effect depends on redistribution from CNS to highly profused areas.
Extensive hepatic metabolism P450 and induce P450 enzymes

50

Etomidate and Propofol

Ionotrophic GABA receptor
Used to enduce conscious sedation prior to surgery.
Enhance activation of GABA-A and at high doses acts as an antagonist. INduce anesthesia in high enough doses

51

Baclofen

Metabatrophic GABA receptror
GABA-B agonist
Used to tx spacicity associated with motor neuron disease.
Mild- oral absorbed slowly, primarily cleared in urine, no tolerance.
Severe- intrathecal- peaks at 4 hours, and tolerance develops after 1-2 years
Withdrawl can precipitate acute hypersensitivity, rhabdomylosis, pruritus, delerium, and fever.

52

Ethanol

Multiple targets including GABA-A and glutamate receptors

53

Chloral hydrate

originally used as anesthetic now used to commit crimes and to prevent memory

54

Gamma hydroxybutyric acid (GHB)

GABA isomer clinical use for narcolepsy, used for crime and date rape

55

Riluzole, memantine, amantadine

NMDA antagoists (block the glutamate receptor, blocks the damage from excitatory)

56

Riluzole

Blocks NA channels therby decreasing glutamate plus acts as an NMDA antagonist (neurodegenerative disease)

57

Memantine and amantadine

Non-competitive blocker of NMDA.
Memantine- alzheimers,
Amantadine decreases dyskinesia in parkinsons

58

Lamotrigine

Stabilizes inactivated state of Na channel reducing excitability and glutamate release
Used in seizures.

59

Felbamate

One mechanism inhibit NMDA receptors- seizures.

60

Tiagabine

competitive inhibitor of GAT-1
Used for epilepsy

61

Vigabatrin

inhibits GABA-T
used as an anticonvulsant

62

a-methyltyosine

inhibits tyrosine hydroxylase (first step in synthesis of catecholamines)

63

Reserpine

Blocks VMAT, transport of bioamines (NE, DA, 5-HT) from cytoplasm into storage vesicles.

64

Tyramine

Dietary amine usually meabolized by MAO in GI and liver. In patients with MAO inhibitors on board tyramine is absorbed, large amounts cause displacement of vesicular NE and non vesicular release leading to hypertensive crisis.

65

Guanethidine

Displaces NE in storage vesicles, leading to gradual depletion of NE.
Will be destroyed by MOA and CTOA

66

Amephetamine

Displaces endogenous NE.
Weak inhibitor of MAO.
Blocks reuptake by NET and DAT
Little agonist action at alpha and beta receptors, marked behavioral effects

67

Cocaine

potent inhibitor of NET, essentially eliminates catecholamine transport
Used as a local anesthetic

68

Imipramine, Fluoxetine

SSRI selective seratonin R inhibitor.
Inhibits NET

69

Tricyclic Antidepressants

Blocks Na+/K+ ATPase, blocks NET
Precents reuptake of epinephrine/norepinephrine leading to an increased DOA.

70

Phenelzine

Inhibits MAO-A, increasing NE and 5-HT (Serotonin) content.
Inhibits metabolism of NE and seratonin

71

Selegiline

Inhibits MAO, increasing DA
Low doses used for tx of Parkinsons

72

Procaine, tetracaine, cocaine

Ester linked anesthetics
Metabolized locally by tissue and plasma esterases
Minutes with short DOA
Eliminated via the kidney

73

Lidocaine, prilocaine, bupivicaine, articaine

Amide linked anesthetics
Primarily P450 in the liver
Metabolites eliminated via kidneys
Longer DOA differing from drug to drug

74

Procaine

Ester based local anesthetic
Short acting, low hydrophobicity- low potency
Used for infiltration anesthesia and dental procedures
Rapidly metabolize in plasma by cholinesterases
One metabolite PABA.

75

Tetracaine

Ester based local anesthetic
long acting, highly potent due to high hydrophobicity
Metabolized by cholinesterase in plasma but slower effect than with procaine as it is slowly released from tissues in the blood.
Spinal and topical anesthesia

76

Cocaine

Natural occurring Ester based local anesthetic
Medium potency and DOA
Inhibits catecholamine uptake peripherally and centerally= vasoconstriction and euphoria (cardiac toxicity)
Ophthalmic and tropical anesthesia

77

Lidocaine and Prilocaine

Amide based
Moderate hydrophobicity, large fraction of drug is in neutral form at physiologic pH= rapid onset, med DOA, and moderate potency
Metabolism by live by P450
Used for peripheral nerve blocks, epidural, spinal, and topical anesthesia.
Toxicities- CNS depression and cardiotoxicity

78

Prilocaine

vasoconstricive

79

Lidocaine

antiarrhythmic

80

Bupivicaine

Amide based
long DOA and highly hydrophobic (high potency)
Metabolized by live P450
R and S enatiomer
Cardiac toxicity due to blocking Na channels in cardiac myocytes during systole but is slow to dissociate during diastole.

81

Articaine

Amide based
Exhibits an ester group making it act differently
Partially metabolized in the plasma by cholinesterase and in the liver by P450

82

Bethanechol- cholinergic agonist

Acts on receptors M1, M2, M3
Poor substrate for AchE
Sites- smooth musculature of the bladder and GI
Actions- increased intestinal motility and tone, and stimulates detrusor muscles of the bladder while the trigone and sphincter are relaxed causing expulsion of urine.
Therapeutic action- stimulates atonic bladder in postpartum or postoperative urinary renention.

83

Bethanechol side effects

sweating, salivation, flushing, HPOTN, N/D, abd pain and bronchospasm.

84

Carbachol (carbamylcholine)

Poor substrate of AchE with DOA of as long as 1hr
Action- M1, M2, M3 and wak nicotinic agonist-CV and GI systems- may first stimulate then depress, can also cause release of epinephrine for adrenal medulla by its nicotinic acitons.
Therapeutics- used seldomly, sometimes as miotic for gluacoma

85

Carbachol (Carbamylcholine) adverse reactions

Little to no side effects when used in the eye

86

Methacholine

Muscarinic Receptor Drug
Receptors- M1, M2, M3
Used as diagnostic challenge for bronchial hyperreactivity and asthmatic conditions

87

Pilocarpine

Muscarinic Receptor Drug
Dominant muscarinic response at M1, M2, M3
Tertiary amine and less potent
Action- rapid miosis and contraction of the ciliary muscle
Therapeutic use- emergency lowering of the intraocular pressure of both narrow and wide-angle glaucoma.

88

Pilocarpine ADR

CNS effects, profuse sweating and salivation

89

Physostigmine

Indirect- acting cholinomimetic drug
Glaucoma (miosis in the eye); increased intestinal and bladder motility, reverse CNS and cardiac effects of TCA (tricyclic antidepressant); reverse CNS effects of atropine.
Action- amplifies effect of Ach

90

Neostigmine, pyridostigmine, edrophonium

Indirect- acting cholinomimetic drug
Myasthenia gravis, helps w/ reversal of neuromuscular block
Action- amplified effects of Ach, increased muscle strength.

91

Isoflurophate and echothiopate

Indirect- acting cholinomimetic drug
Glaucoma (not the 1st line therapy
Action- amplifies the effect of Ach

92

Pralidoxime

Cholinesterase reactivator that breaks bonds between drugs and enzymes if the enzyme has not aged.

93

Celecoxib (celebrex)

may cause an increased risk of serious cardiovascular thrombotic events, MI, and stroke which can be fatal

94

Isotertinoin (Accutane)

Contraindicated in pregnancy
Major human fetal abnormalities, spontaneous abortions, and premature death.

95

Nicotinic receptor drugs- antagonists

Curare, pancuronium, cisatracurium, atacurium, mvacurium, and succinylcholine