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Term 5 Flash Cards > Pharm Exam 1 > Flashcards

Pharm Exam 1 Flashcards

1
Q

Choline esters

A
  • Acetylcholine - very rapidly hydrolyzed.
  • Methacholine - more resistant to hydrolysis.
  • Carbachol and bethanechol - still more resistant to hydrolysis by cholinesterase.
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2
Q

Acetylcholine

A
  • No systemic therapeutic applications dueto multiplicity of actions, and rapid hydrolysis by both acetylcholinesterase and plasma butyrylcholinesterase.
  • Used to obtain rapid miosis after delivery of the lens in cataract surgery and other anterior procedures where rapid miosis is required.
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3
Q

Bethanecol

A
  • Not hydrolyzed by acetylcholinesterase
  • Inactivated by other esterases.
  • Little or no nicotinic actions; strong muscarinic activity.

Uses
• Tx acute post op and postpartum urinary retention.
• Tx neurogenic atony of the urinary bladder with retention.
- Promote GI motility

Adverse effects
• Sweating
• Salivation
• Flushing
• Low blood pressure • Nausea
• Abdominal pain • Diarrhoea
• Bronchospasm

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4
Q

Carbachol

A
  • Both muscarinic and nicotinic agonist.
  • Poor substrate for acetylcholinesterase.
  • Biotransformed by other esterases at much slower rate.

Uses

  • Miosis during surgery
  • Reduces intraocular pressure after cataract surgery
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5
Q

Methacholine

A

• Predominantly muscarinic agonist.

USES
• Dx bronchial airway hyperreactivity in subjects who do not have clinically apparent asthma.

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6
Q

Cholinergic agonists: natural alkaloids

A
  • Muscarine: muscarinic agonist.
  • Arecoline: muscarinic and nicotinic agonist.
  • Pilocarpine: mainly muscarinic.
  • The only natural alkaloid used clinically is pilocarpine: sialagogue and miotic.
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7
Q

Pilocarpine

A

Cholinergic agonist
• Tertiary amine - NOT ammonium! Can cross BBB
• Stable to hydrolysis by acetylcholinesterase.
• Partial muscarinic agonist.

Uses
• Second line agent for open angle glaucoma.
• Management of acute angle-closure glaucoma.

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8
Q

Nicotine actions

A
  • Low doses: ganglionic stimulation by depolarization.
  • The response resembles simultaneous discharge of both parasympathetic and sympathetic nervous systems.
  • CV system: Mainly sympathomimetic effects. Increase in HR and BP due to catecholamine release from adrenergic nerve terminals and from adrenal medulla.
  • GI & urinary tracts: Mainly parasympathomimetic effects: nausea, vomiting, diarrhea, voiding of urine.
  • Secretions: Stimulation of salivary and bronchial secretions.

• High doses: ganglionic blockade and neuromuscular blockade.

  • Symptoms of acute, severe nicotine poisoning: nausea, salivation, abdominal pain, vomiting, diarrhea, cold sweat, mental confusion and weakness.
  • The blood pressure falls, the pulse is weak.
  • Death may occur from paralysis of respiratory muscles and/or central respiratory failure.
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9
Q

Edrophonium

A

Anticholinesterase. Quaternary ammonium. Bindsreversiblytotheactivesite of the enzyme. The enzyme-inhibitor complex doesn’t involve a covalent bond and is short- lived.

USES
• Dx myasthenia gravis. Edrophonium IV leads to rapid increase in muscle strength.
• Also used to reverse neuromuscular block produced by non-depolarizing muscular blockers.

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10
Q

Physostigmine

A

Anticholinesterase. Form a covalent bond with the enzyme. Tertiary amine. Can enter and stimulate CNS.

USES
• Treatment of overdoses of anticholinergic drugs.

NOTE:
• Physostigmine should not be given to a patient with suspected TCA overdose because it can aggravate depression of cardiac conduction.

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11
Q

Neostigmine

A

Anticholinesterase. Form a covalent bond with the enzyme. Quaternary ammonium. Doesn’tenterCNS.

USES
• To stimulate bladder and GI tract.
• Antidote for competitive blockers of the NMJ.
• Symptomatic treatment of myasthenia gravis

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12
Q

Pyridostigmine

A

Anticholinesterase. Form a covalent bond with the enzyme. Quaternary ammonium.

USES
• Treatment of myastheniagravis.
• Most commonly used anticholinesterase for this indication.

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13
Q

Echothiophate

A

Used for glaucoma.

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14
Q

Oral AChE inhibitors used to tx Alzheimer’s dz

A
  • Tacrine
  • Donepezil
  • Rivastigmine
  • Galantamine
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15
Q

Pralidoxime

A

Reactivator of AChE. If given before ageing has occurred, drugs like pralidoxime split the phosphorous-enzyme bond.

• Pralidoxime can be used as cholinesterase regenerator for organophosphate insecticide poisoning.

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16
Q

Atropine

A

Prototype for muscarinic rec antagonists

  • Binds competitively to muscarinic receptors, preventing acetylcholine from binding.
  • Tertiary amine: both central and peripheral muscarinic blocker.
  • Eye: Mydriasis. Cycloplegia.
  • GI: Reduces gastric motility.
  • Urinary system: Decreases hypermotility of urinary bladder.

Cardiovascular system:
• Low doses: bradycardia. Due to blockade of presynaptic M2 receptors that normally inhibit ACh release.
• Moderate to high therapeutic doses: Blockade of atrial M2 receptors: tachycardia.
• High doses of antimuscarinic agents may cause cutaneous vasodilation. This is called ‘atropine flush’. The mechanism is unknown.

Secretions:
• Salivary, sweat and lacrymal gland sare blocked.
• Inhibition of sweat glands may cause high body temperature.

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17
Q

Atropine uses and adverse effects

A

Uses
• Mydriasis and cycloplegia.
• Antispasmodic: to relax GI tract andbladder.
• Antidote for cholinergic agonists.
• Antidote for mushroom poisoning due to muscarine, found in Amanita muscaria and other fungi.
• To block respiratory tract secretions prior to surgery.

Adverse
• Dry mouth, blurred vision, sandy eyes, tachycardia, constipation.
• Effectson CNS: restlessness,confusion, hallucinations, delirium, which may progress to depression, collapse of the circulatory and respiratory systems and death.

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18
Q

Scopolamine

A

Muscarinic antagonist
USES
• Preventionofmotionsickness.
• To block short-term memory: sometimes used in anaesthetic procedures.

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19
Q

Echothiophate

A

Organophosphate. Used to treat glaucoma

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20
Q

Ipratropium and tiotropium

A

Quaternary ammonium muscarinic antagonists.

  • Used as inhalational drugs to tx (COPD).
  • Also used as inhalational drugs inasthma.
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21
Q

Homatropine Cyclopentolate Tropicamide

A

Tertiary amine muscarinic antagonists

  • For use in ophthalmology.
  • Produce mydriasis with cycloplegia.
  • Preferred to atropine bc of shorter duration of action.
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22
Q

Benztropine Trihexyphenidyl

A

Tertiary amine muscarinic antagonists.

• Used to tx parkinsonism and extrapyramidal effects of antipsychotic drugs.

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23
Q

Glycopyrrolate

A

Antimuscarinic agent.

  • Used orally to inhibit GI motility.
  • Used parenterally to prevent bradycardia during surgical procedures.
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24
Q

Tolterodine

A

Antimuscarinic.

• Used for overactive bladder.

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25
Q

Contraindications of antimuscarinic agents

A
  • Contraindicated in pts w/angle-closure glaucoma.
  • Use w/caution in pts w/ BPH and in the elderly.
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26
Q

Hexamethonium Mecamylamine Trimethaphan

A

Nicotinic ganglion blockers.

Used for HTN in in the past.
• D/t their adverse effects they have been replaced by superior antihypertensive agents.

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27
Q

Tubocurarine

A

Nondepolarizing neuromuscular blocker. Competetive agonists.

USES
• As adjuvant drugs in anaesthesia during surgery to relax skeletal muscle.

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28
Q

Succinylcholine

A

Depolarizing neuromuscular blocker.

  • Succinylcholine binds to the nicotinic receptor and depolarizes the junction. Persists in the synaptic cleft, stimulating the receptor: receptor desensitizes.
  • This leads to flaccid paralysis.

USES
• Useful when rapid endotracheal intubation is needed.
• During ECT.

ADVERSE
• Malignant hyperthermia: D/t excessive release of Ca2+ from the SR.
• D/t combinationof succinylcholine and an halogenated anesthetic.
• Treatment: dantrolene.Blocks release of Ca2+ from SR.

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29
Q

Hemicholinium-3

A

Inhibitor of ACh synthesis.

  • Blocks CHT.
  • Prevents uptake of choline required for ACh synthesis.
  • Research tool.
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30
Q

Vesamicol

A

Inhibitor of ACh synthesis.

  • Vesamicol blocks the ACh-H+ antiporter that is used to transport ACh into vesicles, thereby preventing the storage of ACh.
  • Research tool.
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31
Q

Botulinum toxin

A
  • Inhibits acetylcholine release.
  • Injected locally into muscles for treatment of several diseases involving muscle spasms.
  • Also approved for cosmetic treatment of facial wrinkles.
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32
Q

Effects of large dose of IV epinephrine

A

• There is increase in blood pressure. Due to:
1. Increased ventricular contraction (B1 effect).
2. Increased heart rate (B1 effect) This may be
opposed by the baroreceptor reflex.
3. Vasoconstriction (a1 effect).

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33
Q

Effects of low dose of IV epinephrine

A
  • Peripheral resistance decreases, because B2 receptors are more sensitive to epinephrine than a1 receptors. Diastolic pressure falls.
  • Systolic pressure increases due to increased cardiac contractile force (B1 effect).
  • Heart rate increases (B1 effect).
  • There is no increase in mean blood pressure, so the baroreceptor reflex does not kick in.

• Therefore, the effects of epinephrine depend on the dose and the resultant ratio of the B1 to a2 responses in the various vascular beds.

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34
Q

Norepinephrine

A
  • Potent agonist at a1, a2, and B1 receptors
  • Little action on B2 receptors
  • Vasoconstriction: a1effect.
  • Both systolic and diastolic blood pressures increase.
  • Cardiac output is unchanged or decreased.
  • Baroreceptor reflex:
  • The increase in blood pressure induces reflex rise in vagal activity by stimulation of baroreceptors
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35
Q

Dopamine

A
  • Activates dopamine receptors and a and B receptors.
  • Substrate for both MAO and COMT -> ineffective when given orally.

USES
• Drug of choice for shock.
• Increases blood pressure by stimulating heart (a1 effect).
• Increases perfusion to the kidney (D1 effect).
• Superior to norepinephrine that may cause kidney shutdown.

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36
Q

Isoproterenol

A
  • Stimulates B1 and B2 adrenergic receptors.
  • Action on a receptors is insignificant.

CARDIOVASCULAR
• Increases heart rate and force of contraction (B1 effect).
• Dilates arterioles of skeletal muscle (B2effect): decreases peripheral resistance.

PULMONARY
• Bronchodilation (B2 action).

• Can be employed to stimulate heart in emergency situations.

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37
Q

Dobutamine

A
  • The(-)-isomer is an a1 agonist and a weak B1 agonist.
  • The (+)-isomer is an a1 antagonist and a potent B1 agonist.
  • Clinical result: selective B1 agonist.
  • At therapeutic levels the stimulation of B1-receptors predominate, leading to a potent inotropic effect (with little change in heart rate). Net vascular effect is vasodilation (B2-receptors)
  • Used in short-term management of patients with cardiac decompensation (cardiogenic shock, MI)

USES
• Acute management of CHF: Increases cardiac output.
• Increases cardiac output with little change in heart rate.
• Doesn’t significantly elevate O2 demands of the myocardium: major advantage over other sympathetic drugs.

38
Q

B2 adrenergic agonists

A

Used to treat asthma.

SHORT-ACTING
Terbutaline
Albuterol

LONG-ACTING
Salmeterol
Formoterol
• Prolonged duration of action: 12 hours.
• Slow onset of action:not suitable for prompt relief of breakthrough attacks of bronchospasm.

ADVERSE EFFECTS OF B2 AGONISTS
• Tremor, restlessness, apprehension, anxiety, tachycardia.
• Adverse effects are less likely with inhalation therapy than with parenteral or oral therapy.

39
Q

Phenylephrine

A
  • a1 selective prototype.
  • Vasoconstrictor.
  • Nasal decongestant . Given orally or topically.
  • Mydriatic WITHOUT CYCLOPLEGIA (M3-mediated)
  • Used to increase blood pressure in hypotension resulting from vasodilation in septic shock or anesthesia.
  • Used to increase blood pressure and terminate episodes of supraventricular tachycardia.
40
Q

Clonidine

A
  • Partial a2 agonist.
  • Activates central a2-adrenoceptors. Reduces sympathetic outflow by acting on presynaptic a2 adrenergic autoreceptors. This reduces blood pressure.
  • DOES NOT decrease renal blood flow or GFR
  • Used in hypertension management, including hypertensive crises (other drugs with fewer side effects are now generally preferred)

ADVERSE
• Lethargy, sedation, xerostomia.
• Drowsiness, dry mouth, dizziness, headache & sexual dysfunction occur commonly
• Rebound hypertension may occur following abrupt withdrawal (avoid concomitant use with B-blockers)

41
Q

Methyldopa

A
  • Taken up by noradrenergic neurons.
  • Converted to a-methylnorepinephrine which activates central a2-adrenoceptors.
  • Decreases peripheral resistance & decreases  BP (cardiac output NOT decreased )
  • DOES NOT decrease renal blood flow or GFR
  • Drug of choice for treatment of hypertension during pregnancy.

ADVERSE
• Sedation, drowsiness, dizziness, nausea, headache, weakness, fatigue, sexual dysfunction, impaired mental concentration, xerostomia
• Nightmares, mental depression, vertigo (infrequent)
• Development of positive Coombs test (10-20% patients on long-term treatment (>1 year)). Can result in hemolytic anemia, hepatitis & drug fever

42
Q

Brimonidine

A

• Highly selective a2 agonist.
• Given ocularly to lower intraocular pressure in
glaucoma.
• Reduces aqueous humor production and increases outflow.

43
Q

Amphetamine

A
  • Cause norepinephrine release from presynaptic terminals.
  • Potentiate effects of norepinephrine produced endogenously.
  • Has central stimulatory action.
  • Can increase blood pressure by a-agonist action on vasculature as well as B-stimulatory effects on heart.
44
Q

Methylphenidate

A
  • Cause norepinephrine release from presynaptic terminals.
  • Potentiate effects of norepinephrine produced endogenously.
  • Structural analogue of amphetamine.
  • Widely used to treat ADHD in children.
45
Q

Tyramine

A
  • Cause norepinephrine release from presynaptic terminals.
  • Potentiate effects of norepinephrine produced endogenously.
  • Found in fermented foods such as ripe cheese and Chianti wine.
  • Normally oxidized by MAO.
  • If the patient is taking MAO inhibitors, it can precipitate serious vasopressor episodes.

Not used clinically

46
Q

Cocaine

A
  • Blocks monoamine reuptake.
  • Monoamines accumulate in synaptic space.
  • This results in potentiation and prolongation of their central and peripheral actions.
47
Q

Atomoxetine

A
  • Selective inhibitor of the norepinephrine reuptake transporter.
  • Indicated for the treatment of ADHD.
48
Q

Ephedrine

A
  • Induce release of norepinephrine
  • Activate adrenergic receptors.
  • Stimulates a and B receptors and releases norepinephrine from nerve endings.
  • Not a catecholamine -> poor substrate for COMT and MAO -> long duration.
  • Excellent absorption orally and penetrates the CNS.

ACTIONS
• Increases systolic and diastolic blood pressures.
• Causes bronchodilation.
• Mild stimulation of CNS: increases alertness, decreases fatigue and prevents sleep.
• Improves athletic performance.
• Ephedrine-containing herbal supplements were banned by the FDA because of life-threatening CV reactions.

USES
• Used as a pressor agent, particularly during spinal anesthesia when hypotension frequently occurs.
• Used in myasthenia gravis.
• Used in allergic disorders, such as bronchial asthma. Now used infrequently to treat asthma.

49
Q

Pseudoephedrine

A
  • One of four ephedrine enantiomers.
  • Available over the counter as a component of many decongestant mixtures.
50
Q

Phenoxybenzamine

A
  • Irreversible antagonist.
  • Unsuccessful for hypertension.
  • Used in Pheochromocytoma
  • Prior to surgical removal of the tumor.
  • For chronic management of inoperable tumors.
51
Q

Phentolamine

A

• Reversibly blocks a1 and a2 receptors.

USES
• Pheochromocytoma: short term control of hypertension.
• Diagnosis of pheochromocytoma by the phentolamine blocking test.
• Hypertensive crisis associated with stimulant drug overdose.
• Hypertensive crisis due to sudden withdrawal of sympatholytic antihypertensive drugs (eg, clonidine).

52
Q

Epinephrine reversal

A
  • All a-adrenergic blockers reverse the a-agonist effects of epinephrine.
  • The vasoconstrictive a1 action of epinephrineis blocked, but vasodilation caused by activation of B2-receptors is not blocked.
  • Therefore, the systemic blood pressure decreases in response to epinephrine given in the presence of phenoxybenzamine.
53
Q

a1 blockers

A

PRAZOSIN TERAZOSIN DOXAZOSIN TAMSULOSIN
• Selective blockers of the

  • Na+ & H20 retention does occur
  • Effective in lowering BP but more side effects than other antihypertensives

• Concomitant use of a B-blocker may be necessary to blunt short-term effect of reflex tachycardia

54
Q

Terazosin Doxazosin

A
  • Prazosin analogs with longer half-life.
  • Used for hypertension and BPH.

• Doxazosin shown to increase rate of congestive HF

55
Q

Tamsulosin

A
  • Approved for BPH.
  • Little effect on blood pressure.
  • Less likely to cause orthostatic hypotension.
56
Q

Yohimbine

A

a2-adrenergic blocker.

  • Used in the past to treat erectile dysfunction.
  • Phosphodiesterase type 5 inhibitors have replaced it.
57
Q

Propranolol

A
  • Nonselective B-blocker
  • The prototype.
58
Q

Nadolol

A

Non-selective B antagonist

  • Long duration of action.
  • Management of angina pectoris.
  • Management of hypertension.
59
Q

Timolol

A

Non-selective B-antagonist

  • Treatment of hypertension.
  • Prophylaxis of migraine headache.
  • Treatment of intraocular hypertension or open-angle glaucoma.
60
Q

Atenolol Metoprolol

A

B1-adrenergic antagonist

  • Useful in hypertensive patients with impaired pulmonary function.
  • Useful in diabetic hypertensive patients who are receiving insulin or oral hypoglycemic agents.

USES
• Management of hypertension.
• Long-term management of angina pectoris.
• Management of MI to reduce CV mortality.

61
Q

Esmolol

A
  • Ultra-short acting B1-selective adrenergic antagonist.
  • Half life of 10minutes. Used as antiarrhythmic
  • Given IV.

USES
• Supraventricular arrhythmias.
• Arrhythmias associated with thyrotoxicosis.
• Perioperative hypertension.
• Myocardial ischemia in acutely ill patients.

62
Q

Labetalol

A

• Competitive antagonist at B and a1 receptors.
• Substantially more potent as a B-antagonist than
a-antagonist.

USES
• Oral & parenteral admin.
• Used in hypertension management (safe in pregnancy)
• IV labetalol = rapid reduction in BP -> useful in hypertensive emergencies
• Management of hypertension.
• Advantages: Decrease in BP associated with a1-blockade DOES NOT CAUSE reflex increase in HR or cardiac output

ADVERSE
• Orthostatic hypotension may be a problem (first use or high doses)

CONTRAINDICATIONS
Asthma, COPD, patients with 2nd or 3rd-degree AV block or bradycardia

63
Q

Carvedilol

A

• Competitive antagonist at B and a1 receptors.

  • Like labetalol, it is substantially more potent as a B-antagonist than a-antagonist.
  • Also has antioxidant properties.
  • Used in hypertension and congestive heart failure.
64
Q

Pindolol

A
  • Partial B agonist. Said to have intrinsic sympathomimetic activity (ISA).
  • They may be preferred as antihypertensives in individuals with diminished cardiac reserve or a propensity to bradycardia.
  • The clinical significance of partial agonism has not been demonstrated in controlled trials, but may be of importance in individual patients.
  • Preferred B-blocker in pregnancy
65
Q

a-methyltyrosine (metyrosine)

A
  • Competitive inhibitor of tyrosine hydroxylase.
  • Used for management of malignant pheochromocytoma.
  • Used in preoperative preparation of patients for resection of pheochromocytoma.
66
Q

Reserpine

A
  • Irreversibly damages VMAT. Vesicles cannot store norepinephrine and dopamine.
  • This causes depletion of norepinephrine, since MAO degrades norepinephrine in the cytoplasm.
  • Gradual decrease in blood pressure and slowing of cardiac rate.
  • Used in the past to treat hypertension.
67
Q

Guanethidine

A
  • Guanethidine displaces norepinephrine from transmitter vesicles leading to depletion of norepinephrine.
  • Additionally, guanethidine inhibits release of norepinephrine. This action is primarily responsible for its antihypertensive action.
  • Guanethidine causes a gradual decrease in blood pressure and heart rate.
  • In the early 1970s guanethidine was a major antihypertensive drug for severely hypertensive patients.
68
Q

Cromolyn Nedocromil

A

Histamine antagonist.

  • Reduce immunologic mast cell degranulation.
  • B2-agonists also appear capable of reducing histamine release.
69
Q

First gen H1 rec antagonists

A
  • Chlorpheniramine
  • Diphenhydramine
  • Dimenhydrinate
  • Doxylamine
  • Hydroxyzine
  • Meclizine
  • Promethazine
70
Q

Second gen H1 rec antagonists

A
  • Fexofenadine
  • Loratadine
  • Cetirizine
  • Acrivastine
71
Q

Terfenadine Astemizole

A

Histamine rec antagonists. K+ channel blockers (repolarization). Can cause cardiac arrhythmias when taken with CYP3A4 inhibitors.

Taken off the US market.

72
Q

H2 rec antagonists

A
  • Cimetidine
  • Ranitidine
  • Famotidine
  • Nizatidine
  • Main clinical use: inhibitors of gastric acid secretion.
  • By competitively blocking H2 receptors, these agents reduce secretion of gastric acid.
73
Q

Actions and uses of H1 blockers

A

ACTIONS
• Inverse antagonists of H1 receptors.
• First-generation H1 antagonists have additional effects due to blocking of cholinergic, a- adrenergic, serotonin and local anesthetic receptor sites.

USES
• Drugs of choice for allergic rhinitis and urticaria because histamine is the principal mediator.
• Ineffective in bronchial asthma because histamine is only one of several mediators.
• Certain H1 receptor blockers are effective agents for prevention of symptoms of motion sickness.
• Some first-generation H1 blockers have strong sedative properties and are used in the treatment of insomnia.

ADVERSE
• Sedation: less common with second generation agents.
• Dry mouth: due to anticholinergic effects.

74
Q

H2 rec antagonist adverse effects

A

ADVERSE
• H2 antagonists are extremely safe drugs.
• Adverse effects occur in less than 3% of patients.
• Include: headache, dizziness, diarrhea, muscular pain, constipation.
• Confusion, hallucinations and agitation may occur when given IV, especially in patients in the ICU who are elderly or who have renal or hepatic dysfunction.
• These adverse effects may be more common with cimetidine.

  • Cimetidine inhibits cytochrome P450 and can slow metabolism of several drugs.
  • Cimetidine binds to androgen receptors and has antiandrogenic effects: gynecomastia and reduced sperm count in men and galactorrhea in women.
75
Q

Sumatriptan

A

5-HT1D/1B rec agonist prototype.

Triptans are first-line therapy for acute severe migraine attacks.

76
Q

Metoclopramide

A

5-HT4 agonist.

  • Prokinetic agent.
  • Its administration results in coordinated contractions that enhance GI transit.
77
Q

Cisapride

A

5-HT4 agonists.

• Prokinetic agent.
• Due to serious cardiac adverse effects it is no
longer generally available in the US.
• The drug is available only on a limited basis.

78
Q

Cyproheptadine

A

5-HT2 rec antagonist.
• Also has potent H1 blocking actions.

USES
• Allergic rhinitis
• Vasomotor rhinitis
• Management of serotonin syndrome.

79
Q

Ondansetron

A

5-HT3 rec antagonist

  • Anti-emetic.
  • Particularly for the severe nausea and vomiting that occurs with cancer chemotherapy.
80
Q

Ergot alkaloids

A
  • Produced by Claviceps purpurea, a fungus that infects grain.
  • These alkaloids affect a adrenoceptors, 5-HT receptors and CNS dopamine receptors.
81
Q

Ergotamine Dihydroergotamine

A
  • Ergot derivatives are highly specific fo rmigraine pain.
  • Triptans are preferred, but therapy with ergotamine or dihydroergotamine can be effective.
82
Q

Bromocriptine Cabergoline

A

• Tx hyper-PRLemia. Effectivein reducing the high levels of prolactin that result from pituitary tumors.

83
Q

Ergonovine Methylergonovine

A

Tx postpartum hemorrhage.
Oxytocin is the preferred agent for control of postpartum hemorrhage, but if it is ineffective, ergonovine or methylergonovine IM can be tried.

Dx variant angina.
Ergonovine IV provokes coronary artery spasm in patients with variant angina.

84
Q

Use of eicosanoids for obstetrics

A

• Dinoprostone(PGE2),andmisoprostol(a
PGE1analog): to ripen the cervix at or near term.
• Carboprost tromethamine (15-methyl-PGF2a), and misoprostol: for management of postpartum hemorrhage.
• Dinoprostone & carboprost tromethamine: used as abortifacients.
• Misoprostol:usedincombinationwiththe antiprogestin mifepristone or with methotrexate as abortifacient.

85
Q

Alprostadil (PGE1)

A

Eicosanoid

  • Used to maintain patency of the ductus arteriosus in peds.
  • Used for impotency in urology
86
Q

Epoprostenol (PGI2)

A

Eicosanoid.

Used in severe pulmonary hypertension.
• Lowers peripheral, pulmonary, and coronary resistance • Given via continuous infusion
• Adverse effects include flushing, headache, jaw pain, diarrhea and arthralgias

• Also used to prevent platelet aggregation in dialysis machines.

87
Q

Misoprostol

A

Eicosanoid.

For prevention of peptic ulcers in patients taking high doses of NSAIDs.

88
Q

Latanoprost

A

Eicosanoid. a PGF2-a derivative.

Gold standard for glaucoma.

89
Q

Zileuton

A

Inhibition of 5-lypoxygenase

90
Q

Zafirlukast Montelukast

A

• Inhibition of the binding of LTD4 to its receptor
in target tissues

Term 5 Flash Cards (16 decks)

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