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110 Cards in this Set
- Front
- Back
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Histamine at H1 Receptor does what?
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H1 receptor
Bronchoconstriction- increases IP3 + DAG= increase in Ca2+ Intestinal smooth muscle contraction- IP3 + DAG= increase in Ca2+ Inotropic and Chronotropic effects- reflex increase in HR due to vasodilation Vasodilation- increase in NO Increased capillary permeability- contraction of endothelial cells |
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Histamine at H2 Receptor does what?
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H2 Receptor
Gastric Acid Secretion Inotropic and Chronotropic effects- increase contraction and HR Vasodilation- increase in cAMP |
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cAMP effect of Histamine release?
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cAMP inhibits histamine release
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cGMP effect of Histamine release?
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cGMP enhances histamine release
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What is required for degranulation?
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1. Ca2+
2. cellular energy 3. enzymatic reaction 4. aggregation of microtubules |
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Name the Histamine receptor involved:
Bronchoconstriction Contraction of intestinal smooth muscle Gastric acid secretion Inotropic and Chronotropic effects Vasodilation Increased capillary permeability Decreased neurotransmitter release |
Name the Histamine receptor involved:
Bronchoconstriction- H1 Contraction of intestinal smooth muscle- H1 Gastric acid secretion-H2 Inotropic and Chronotropic effects- H1 and H2 Vasodilation- H1 and H2 Increased capillary permeability- H1 Decreased neurotransmitter release- H3 |
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H2 agonist
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Betazole
used to test for ability to secrete gastric acid |
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Histamine release inhibitors
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1. Cromolyn sodium
2. Nedocromil 3. Beta agonists Prophylactic use for asthma inhibits antigen induced release of histamine from sensitized mast cells |
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Uses of H1 blockers (antihistamine)
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1. Treat allergic reactions
2. Anaphylaxis and serum sickness 3. Motion sickness 4. Use as hypnotic |
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Class of antihistamines most used for Motion Sickness
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Piperazine
meclizine and cyclizine, etc. |
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Which class of antihistamines are most used as hypnotics?
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Ethanolamines
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What is Cromolyn sodium?
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Cromolyn sodium (Intal)
inhibits histamine release reduce degranulation of mast cells used as prophylactic treatment for bronchial asthma No bronchodilator or anti-inflammatory actions |
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What is Nedocromil?
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Nedocromil (Tilade)
inhibits histamine release reduce degranulation of mast cells used as prophylactic treatment for bronchial asthma No bronchodilator or anti-inflammatory actions |
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Name the Ethalonamines
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1. Diphenhydramine
2. Dimenhydrinate 3. Doxylamine 4. Clemastine |
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Name the Ethylenediamines
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Tripelnnamine (aka pyribenzamine, PBZ)
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Name the Piperazines
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1. Meclizine
2. Cyclizine 3. Hydroxyzine pamoate 4. Hydroxyzine HCl |
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Name the Alkylamines
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1. Brompheniramine
2. Chlorpheniramine |
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Name the Phenothiazines
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Promethazine
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Name the Second Generation Antihistamines
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1. Terfenadine and Astemizole
2. Loratidine 3. Desloratidine 4. Cetirizine 5. Fexofenadine |
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What is Diphenhydramine?
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Diphenhydramine (Benadryl)
Potent anticholinergic effects, highly sedative, anti-emetic activity also local anesthetic activity due to its ability to block Na channels; sometimes used to treat the tremor of early parkinson's disease |
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What is Dimenhydrinate?
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Dimenhydrinate (Dramamine)
Ethalonamine: Potent anticholinergic effects, highly sedative, anti-emetic activity used extensively to combat motion sickness |
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What is Doxylamine?
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Doxylamine (Unisom)
Ethalonamine: Potent anticholinergic effects, highly sedative, anti-emetic activity originally marketed at Bendectin for morning sickness; used only as sleep aid |
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What is Clemastine?
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Clemastine (Tavist)
Ethalonamine: Potent anticholinergic effects, highly sedative, anti-emetic activity |
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What is Tripelennamine?
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Tripelennamine (aka pyribenzamine, PBZ)
Ethylenediamine: less anticholinergic, less potent antihistamine, moderate sedation T's and Blues |
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What is Meclizine?
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Meclizine (Bonine, Antivert)
Piperazine: less anticholinergic activity, similar antihistamine potency, used to treat motion sickness, slight sedative properties; potential for teratogenic effects Anti-Motion sickness agents |
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What is Cyclizine?
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Cyclizine (Marezine)
Piperazine: less anticholinergic activity, similar antihistamine potency, used to treat motion sickness, slight sedative properties; potential for teratogenic effects Anti-motion sickness agents |
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What is Hydroxyzine pamoate?
What is Hydroxyzine HCl? |
Hydroxyzine pamoate (Vistaril)
Hydroxyzine HCl (Atarax) Piperazines: less anticholinergic activity, similar antihistamine potency, used to treat motion sickness, slight sedative properties; potential for teratogenic effects Used for mild anxiety; anxiolytic |
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What is Brompheniramine?
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Bropheniramine (Dimetapp)
Alkylamine: most potent antihistamines; moderate anticholinergic effects; greatest use is in OTC cold medications |
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What is Chlorpheniramine?
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Chlorpheniramine (Chlor-Trimetron)
Alkylamine: most potent antihistamines; moderate anticholinergic effects; greatest use is in OTC cold medications |
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What is Promethazine?
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Promethazine (Phenergan)
Phenothiazine: greatest anticholinergic, marked sedation and anti-emetic activity mild antagonistic action at D2 dopamine receptors also posses local anesthetic activity |
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What is Cyproheptadine?
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Cyproheptadine (Periactin)
H1 blocking activity with 5HT2A and 5HT2C receptor antagonism Uses: counteract SSRI and TCA induced sexual dysfunction; appetite stimulant; treatment of cold urticaria |
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What is Terfenadine?
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Terfenadine (Seldane)
Second Generation Antihistamine: H1 receptor blocker not capable of crosses BBB, minimal sedative effects prolongs QT metabolized by CYP450 Removed from market |
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What is Astemizole?
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Astemizole (Hisminal)
Second Generation Antihistamine: H1 receptor blocker not capable of crosses BBB, minimal sedative effects prolongs QT metabolized by CYP450 Removed from market |
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What is Loratidine?
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Loratidine (Claritin)
Second Generation Antihistamine: H1 receptor blocker not capable of crosses BBB, minimal sedative effects does NOT prolong QT NOTE: Take on empty stomach |
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What is Desloratidine?
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Desloratidine (Clarinex)
Second Generation Antihistamine: H1 receptor blocker not capable of crosses BBB, minimal sedative effects does NOT prolong QT NOTE: okay with or without food |
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What is Cetirizine?
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Cetirizine (Zyrtec)
Second Generation Antihistamine: H1 receptor blocker not capable of crosses BBB, minimal sedative effects metabolite of hydroxyzine |
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What is Fexofenadine?
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Fexofenadine (Allegra)
Second Generation Antihistamine: H1 receptor blocker not capable of crosses BBB, minimal sedative effects metabolite of terfenadine does NOT prolong QT can be taken up to twice daily |
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Classes of Antihistamines with most Anticholinergic Potency
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1. Ethanolamines
2. Phenothiazines |
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Name aggressive/erosive factors in Gastrointestinal Acid-Peptic Disorders
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1. Hydrochloric Acid
2. Pepsin 3. Bile salts 4. Bacterial pathogens 5. drugs (NSAIDs, alcohol) |
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What stimulates gastrin release?
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1. protein
2. vagal stimulation (PSNS) 3. Calcium ion 4. mechanical distention by food 5. increased gastric pH |
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Name the common types of Antacids
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1. Sodium bicarbonate (GAS)
2. Calcium carbonate 3. Magnesium salts 4. Aluminum salts |
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Key points to remember about Calcium Carbonate?
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Calcium Carbonate
dissolves more slowly than sodium bicarbonate too high of intake can lead to "milk alkali syndrome"- nausea, vomiting, weakness, myalgia, memory loss, lethary, stupor, coma may produce gastric acid hypersecretion and reboud |
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Key points to remember about Magnesium salts?
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moderate reaction rate
excess Mg due to renal impairment may cause hypotension, naseau, vomiting, ECG changes, respiratory, and mental depression Side effect: DIARRHEA |
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Key points to remember about Aluminum salts?
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dissolves slowly
Side effect: CONSTIPATION possible connection with encephalopathy and Alzheimers combines with phosphate so it can cause hypercalcemia, osteoporosis, osteomalacia all due to low phosphate levels |
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Parietal cells secrete what?
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HCL and intrinsic factor
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Chief cells secrete what?
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pepsinogen
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G-cells secrete what?
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Gastrin into the bloodstream
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What cells secrete mucous and bicarbonate?
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Superficial epithelial cells (EP3)
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Name an anti-muscarinic agent used as an antisecretory GI agent
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Atropine
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Side effects of Antimuscarinics
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1. tachycardia
2. dry mouth 3. blurred vision 4. drowsiness 5. urinary retention 6. constipation 7. slow esophageal motility 8. contraindicated in GERD and glaucoma |
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Name H2 antagonists
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Cimetidine
Ranitidine Famotidine Nizatidine ALL are competitve inhibitors of histamine at H2 receptor Potency: Famotidine>Nizatidine>Ranitidine>Cimetidine |
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What is Cimetidine
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Cimetidine (Tagamet)
H2 antagonist crosses BBB Causes confusion in the elderly Treats Zollinger-Ellison syndrome and Systemic Mastocytosis Side effects: gynecomastia, decreased sperm count, inhibits CYP450 (drug interactions) |
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What is Ranitidine
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Ranitidine (Zantac)
H2 antagonist undergoes significant first pass metabolsim; little effect on CYP450; more water soluble and hydrophilic than cimetidine (NO CNS activity) |
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What is Famotidine
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Famotidine (Pepcid)
Most potent H2 Antagonist long-acting agent because it binds very tightly and released slowly |
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What is Nizatidine
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Nizatidine (Axid)
H2 Antagonist Side effects: somnolence, sweating, urticardia 100% bioavailability |
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What is Zollinger-Ellison syndrome
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excessive gastrin secretion from pancreatic delta cell tumors
treat with Cimetidine (Tagamet) |
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What is Systemic mastocytosis
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increased proliferation and organ infiltration by mast cells
treat with Cimetidine (Tagamet) |
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Name the Proton Pump Inhibitors (PPIs)
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1. Omeprazole (Prilosec)
2. Esomeprazole (Nexium) 3. Lansoprazole (Prevacid) 4. Pantoprazole (Protonix) 5. Rabeprazole (Acifex) |
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How do PPI work?
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irreversible inhibition of H+/K+ ATPase due to oxidation of -SH
they are prodrugs and need the acidic environment to activate them Cannot be crushed or cut; formulation should be microgranules or enteric coated Best to take 30 minutes prior to meals |
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Intisecretory GI drug involving Prostaglandins
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Misoprostol (Cytotec)
Synthetic PGE |
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What is Misoprostol
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Intisecretory GI drug involving Prostaglandins- synthetic PGE
offers cytoprotection at low dose and anti-secretory effects at higher doses adjunctive therapy to NSAIDs can cause abortion since PGs stimulate uterine contractions Side Effect: DIARRHEA- inhibits intestinal segmental contractions Avoid in IBS |
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What is Sucralfate?
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Sucralfate (Carafate)
aluminum salt of sucrose containing 8 sulfate groups; becomes negatively charged at pH less than 3 and polymerizes to form a viscous paste which adheres to gastric and duodenal mucosa.... ulcer craters Has NO acid neutralizing properties DO NOT give to patients with renal failure |
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What is Bismuth Subsalicylate?
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Bismuth Subsalicylate (Pepto-Bismol)
enhances secretion of mucus and bicarbonate; inhibits pepsin activity; antibacterial effects against H pylori stool may turn black due to H2S |
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What is the current treatment for too much H. Pylori
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Triple Therapy:
Metronidazole bismuth compound tetracycline or amoxicillin for two weeks combined with H2 receptor blockers or PPIs |
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Name GI agents that promote stimulation
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1. ACh- M3 receptor
2. Serotonin- at 5-HT4 receptor 3. Motilin 4, Serotonin- at 5-HT3 receptor 5. CCK- stimulation in the intestines |
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Causes for GI inhibition
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1. sympathetic stimulation
2. activation of dopamine receptors 3. NO and VIP 4.5-HT1A increases NO release |
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Name the Prokinetic Agents
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1. Metoclopramide (Reglan)
2. Domperidone (Motilium) 3. Cisapride (Propulsid) 4., Tegaserod (Zelnorm)- DC 5. Erythromycin |
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Name the Anti-Motility Agents
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1. Alosetron (Lotronex)
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What is Metoclopramide?
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Metoclopramide (Reglan)
Prokinetic Agent enhances motility of smooth muscle from esophagus through to ileocecal valve MOA: -D2 dopamine receptor antagonist -5-HT receptor partial agonist -sensitizes muscarinic activity USES: gastroparesis, esophageal reflux, nausea and vomiting (including pregnancy), and emesis resulting from cancer chemotherapy |
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What is Domperidone?
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Domperidone (Motilium)
Prokinetic Agent Antagonizes D2 receptors; does NOT penetrate well into CNS Uses: anti-emetic and to produce hyperprolactemia |
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What is Cisapride?
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Cisapride (Propulsid)
Prokinetic Agent increases motility thru the colon and can cause diarrhea MOA: agonist at presynaptic 5-HT 4 receptors on submucosal IPANS; therefore, increasing the release of CGRP and ACh It also works on motor neurons to increase the release of ACh onto smooth muscle cells Does NOT block D2 receptors (NO effect on prolactin) Plasma levels are higher if taken with food; metabolized by CYP3A4 Drug interactions: prolongs QT interval erythromycin, ketoconazole, nefazadone, grapefruit juice all inhibit CYP3A4 |
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What is Tegaserod?
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Tegaserod (Zelnorm)
Prokinetic Agent Discontinued 5-HT4 receptor partial agonist used for short term treatment of women with IBS with constipation |
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What is Erythromycin?
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Erythromycin
Prokinetic Agent stimulates motilin receptors directly to promote onset of a migrating motor complex toleerance develops rapidly |
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What is Alosetron?
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Alosetrin (Lotronex)
Anti-Motility Agent 5-HT3 receptor antagonist USE: treat women with IBS with predominant DIARRHEA only physicians enrolled in GlaxoSmithKline's prescribing programs should prescribe alosetron |
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What is Lubiprostone?
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Lubiprostone (Amitza)
Treats chronic idiopathic constipation; the drug is a prostaglandin E1 (PGE1) derivative increases intestinal fluid by activating opening specific chloride channels (ClC-2 Type); this causes chlorine rich intestinal fluid secretion which softens the stool, increases motility in the intestine, and promotes spontaneous bowel movements |
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What blocks the rate-limiting step of Tryptophan to Serotonin?
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Chlorphenylalanin inhibits tryptophan 5-hydroxylase
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Where is Serotonin located in the body?
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90%= enterochromaffin cells of the intestine
8%= plateletes 2%= CNS |
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What does 5HT-1 receptor do?
subtype 1A subtype 1B subtype 1D |
5HT-1 receptor
found predominantly in the brain Activation of 5HT-1: 1. decrease cAMP 2. open K channel= hyperpolarization subtype 1A= inhibitory autoreceptor subtype 1B and 1D= inhibit neuron release agonist action at 1B and 1D results in inhibition of dural neurogenic inflammation, plasma extravasation, and vasodilation associated with migrane |
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Effects of 5-HT2 receptors?
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5-HT2 stimulation causes contriction of vascular and intestinal smooth muscle; linked to PIP2 hydrolysis (increase DAG and IP3)
activation of 5-HT2 receptors on endothelial cells stimulates the release of NO and prostaglandins... relaxation |
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Effects of 5-HT3 receptors?
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5-HT3 receptor is actually a serotonin gated Na+ channel; binding of 5-HT to this receptor opens the channel leading to rapid depolarization (excitation) or neurons
stimulation in the GI tract or brainstem chemoreceptor trigger zone (CTZ) induces nausea and vomiting stimulation of the peripheral sensory neurons causes pain |
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What are the effects of 5-HT4 receptors?
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5-HT4 receptor activation leads to an increase in adenylyl cyclase activity which increases cAMP levels
stimulation leads to neuronal excitation in the GI tract and hippocampus Activation in the GI tract produces secretion and facilitates peristalsis |
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How does Serotonin effect the following:
1. Cardiovascular system 2. Respiratory system 3. Central Nervous system 4. Peripheral nervous system 5. Gastrointestinal tract 6. Skeletol Muscle |
How does Serotonin effect the following:
1. Cardiovascular system- intitial decrease in BP, then increase in BP, then decrease in BP again 2. Respiratory system- contracts bronchial smooth muscle and can cause hyperventilation 3. Central Nervous system- accelerates sleep onset, prolongs sleep time, temperature regulation, controls mood and behavior 4. Peripheral nervous system- bradycardia, hypotension, and apnea 5. Gastrointestinal tract- increases tone and facilitates peristalsis; increases ACh release 6. Skeletal Muscle- unknown |
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Name the 5-HT 1B/1D agonists
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Sumatriptan (Imitrex)
Zolmitriptan (Zomig) Rizatriptan (Maxalt) Naratriptan (Amerge) Almotriptan (Axert) Eletriptan (Relpax) Frovatriptin (Frova) |
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How do the Triptans work?
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stimulation of 5HT-1D inhibits release of vasodilating peptides Substance P, Neurokinin A, and CGRP therefore, the vasodilation and mast cell activation leading to inflammatory process is hindered
5HT-1B receptor activation on the smooth muscle of blood vessels causes vasocontriction and constricts anastomoses at smooth muscle of arteriovenous anastomostes Efffective in treaty ANY stage of migraine |
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Which 5-HT 1B/1D agonist has the longest half life
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Frovatriptan (Frova)
least likely to have rebound headache |
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What are the main side effects of 5-HT 1B/1D agonists?
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Triptans
fatigue, sedation, weakness, pressure sensation, tightness/pressure in chest, neck or throat, tingling/paresthesias, dizziness/vertigo, feeling of heat/warmth |
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What are the contraindications for 5-HT 1B/1D agonists
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use of ergotamine, DHE, or other ergot preparations withing the prior 24 hrs
use of MOAI withing the past 2 weeks-serotonin syndrome Heavy smoking/uncontrolled hyptertension myocardial infarction or silent myocardial ischemia strong family history of coronary heart disease Prinzmetal's angina children or pregnant women caution in renal impairment, seizure disorders, cerebral ischemia, brain hemorrhage |
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Prodrome vs Aura
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Prodrome= day prior to migraine
Aura= within a few hours of migraine |
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What do 5 HT-3 Receptor Antagonists treat
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1. Anti-emetic
2. IBS with predominant diarrhea (Discontinued) |
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Name the 5-HT3 Receptor Antagonists used as anti-emetics
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1. Ondasteron (Zofran)
2. Granisetron (Kytril) 3. Dolasetron (Anzemet) 4. Palonsetron (Aloxi) |
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What is Alosetron?
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Alosetron (Lotronex)
5-HT3 receptor antagonist that was used for treating women with irritable bowel syndrome with predominant diarrhea Withdrawn from market in 2000 Re-introduced but physicians must be inrolled in Glaxo Smith Kline prescribing program |
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What is Cyproheptadine?
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Cyproheptadine (Periactin)
5-HT 2A/2C and H1 receptor antagonist treats seasonal allergic rhinitus, chronic urticaria, appetite stimulant, intesinal hypermotility, reduces ACTH secretion in Cushings disease, counteract sexual disfunction brought about by SSRI use |
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Name the Serotonin Parital Agonists
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1. Tegaserod (Zelnorm)
2. Metoclopramide |
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What is Tegaserod?
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Tegaserod (Zelnorm)
Serotonin Partial agonist at 5-HT4 receptor indicated for women with irritable bowel syndrome with primary symptom of constipation |
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What is Metoclopramide?
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Metoclopramide
Serotonin Partial Agonist at 5-HT4 receptor and also antagonizes D2 receptors and also weak 5-HT3 agonist |
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What receptors are in the Vomiting Center (STN)?
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Vomiting Center:
5-HT3 blockade H1 blockade Muscarinic blockade NK-1, 5HT, and CB |
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What receptors are in the Chemoreceptor Trigger Zone (CTZ)?
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Chemoreceptor Trigger Zone (CTZ):
Dopamine antagonists (D2) Serotonin Antagonists (5-HT3 blockade) u-opiod CB1 Muscarinic |
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What receptors are in the Labyrinth Apparatus?
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Labyrinth Apparatus:
Antihistamine (H1 blockade) M1 receptor |
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Name antihistamines-anticholinergics used to treat emesis
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Diphenhydramine
Hydroxyzine Trimethobenzamide Promethazine |
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Name Dopamine antagonists used to treat emesis
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Phenothiazines: Prochlorperazine (Compazine)
Butyrophenones: Droperidol and Haloperidol Benzamides: Metoclopramide |
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Corticosteroid used to treat emesis
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Dexamethasone used to treat acute and delayed emesis
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Benzodiazepine used to treat emesis
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Lorazepam (Ativan) used for anticipatory nausea and vomiting
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Name the Neurokinin-1 Receptor Antagonists used to treat Emesis
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Aprepitant (PO)
Fosaprepitant (IV) |
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What are the main effects of ergot poisoning?
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1. dementia with florid hallucinations
2. prolonged vasospasm- can lead to gangrene (Saint Anthony's Fire) 3. Uterine contractions- may result in abortion |
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Ergots used to treat postpartum hemorrhage
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1. Ergonovine (Ergotrate)
2. Methylergonovine (Methergine) |
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What are the signs of Ergot toxicity
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N/V, diarrhea, thirst, pruritus, vertigo, muscle cramps, parasthesias, cold skin, gangrene
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Name the Ergots used for Migraine Headaches
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1. Ergotamine- when combined with caffeine it is called Cafergot
2. Dihydroergotamine mesylate (DHE-45)-only injectable form of ergot 3. Methysergide (Sansert)- can only be used as prophylaxis of migraine; weak 5-HT2 receptor partial agonist; also inhibits endothelial release of NO |
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What do you have to be careful of with Methysergide
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must not exceed 6 months; must have 3-4 week drug free interval after each 6 months course
Retroperitoneal fibrosis, pulmonary fibrosis, thickening of the aortic and mitral valves may occur upon prolonged therapy |
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What drugs can be used to treat hyperprolactemia?
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1. Bromocriptine mesylate (Parlodel)
2.Pergolide (Permax) D2 agonist effects which inhibit prolactin release from the anterior pituitary |
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What drugs can be used to treat Parkinson's disease?
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Bromocriptine
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