pharm exam 3 Flashcards
phase 0
the cell enters a point of stimulation
-Na+ (sodium) rushes into the cell and depolarization occurs
phase 1
short period when sodium ion channels close and decrease permeability of NA+
-repolarization as K+ potassium leaves the cell
phase 2
-permeability to K+ decreases and calcium enters the cell
-action potential lasts longer
phase 3
rapid repolarization period
-Ca2+ stops and K+ permeability increses rapid rush of potassium out
-membrane back to resting state
phase 4
cell is resting membrane potential
-sodium-potassium pump
class 1 antiarrhythmic
-blocks sodium channels in cell membrane
-depressed phase 0
-prolonged duration of action potential
-quinidine, procainamide 1a
-lidocaine 1b
-flecainide, propafenone 1c
lidocaine
-ventricular dysrhythmias
-bolus injection
-anesthetic agen
flecainide and propafenone
paraxysmal afib/flutter
-maintains normal sinus rythym
quinidine
-grapefruit juice interferes with metabolism causing toxic levels
class 2 antiarrhythmic
block beta receptors
-depressed phase 4
-esmolol, propranolol, adenosine
esmolol and propranolol
-avoid in asthmatic clients and cause bronchospasms
adenosine
-6mg rapid IV over 1-2 seconds
-can do 2nd dose 1-2 minutes later at 12mg x2
-converts SVT to sinus rhythm
-15 sec duration of action
-athmatic client caution
-flushing, headaches, dyspnea (short term)
class 3 antiarrhythmic
-block potassium channels and prolong phase 3 (potassium leaves slowly)
-amiodarone, dofetilide, sotalol, dronedarone, ibutilide
amiodarone
-treats life threatending vertricular dysrhythmias, ven. fib, pulseless ven. tachycardia
-drug of choice for cardiac arrest
-converts afib to normal sinus rhythm
amiodarone adverse effects
-QT prolongation
-bradycardia
-hypotension
-GI
-hepatotoxicity
-pulmonary toxic
-hyper/hypo thyroid
-blue-gray skin
-photosensitivity
class 4 antiarrhythmic
-calcium channel blockers
-block movement of Ca2+ across membrane in cardiac and smooth muscle cells
-depressing phases 1 and 2
-slows automaticity and conduction and ventricular rate
-non-dihydropyridines: diltiazem, verapamil
class 4 antiarrhythmic indications and adverse effects
indications: treats supraventricle dysrhythmias, supraventricle tachycardia, afib, a flutter, angina, and hyper tension
adverse : bradycardia, tachycardia, AV block
antianginal agents
-improve blood flow to the heart muscle (myocardium) by dilating vessels, increasing oxygen supply, and decreasing work of the heart
-nitrates, beta-adrenergic blockers, and calcium channel blockers
-used for all the anginas and STEMI/NSTEMI
ranolazine
-ranexa
-treats chronic angina
nitrates antianginal
-nitroglycerin
-directly on smooth muscle to relax and depress muscle tone
-relaxes and dilate veins, increasing blood flow through vessels and lowers BP because decrease in resistance
-decreases preload and afterload
nitroglycerin adverse effects
-headache, hypotension, dizziness, reflex tachycardia, syncope
nitroglycerin drug drug interactions
-heparin: decreases effect
-do not combine with phosphodiesterase type 5 PDE5
ihibitors like sildenafil (viagra), tadalafil, and vardenafil because it can cause serious hypotension
administering nitroglycerin
-1 tablet under tongue every 5 minutes PRN for a total of 3 tablets
-take BP before 1 dose and before any subsequent dose hold for hypotension
beta blockers antianginal
block sympathetic nervous system stimulation causing a decrease in cardiac output, myocardial oxygen consumption, excitability of the heart, and BP
-atenolol, metoprolol tartrate and succinate, propranolol, nadolol LOL
calcium channel blockers antianginal
-decrease preload and after load, which reduces cardiac workload and oxygen consumption
-dihydropyridines: amlodipine, nifedipine (lower BP)
-non-dihydropyridines: diltiazem, verapamil (lower HR, BP)
-prinzmetal angina, chronic angina, exertional angina
peptic ulcer disease causes
-bacterial infection :helicobacter pylori
-Nsaid usage (COX1)
-acute physiological stress which activates the SNS and decreases flow to GI leading to erosion of stomach lining (trauma, burns, illness)
gastroesophageal reflux disease (GERD)
- digestive disorder that affects lower esophogeal sphincter
-stomach acid flows back into esophogus and can irritate the lining
-symptoms: heartburn, dysphagia, chest pain, regurgitation, “lump in the throat”
GI disorder drugs: Histamine-2 antagonists
-block release of hydrochloric acid in response to gastrin
-famotidine (pepcid), cimetidine (tagmet)
Histamine 2 antagonists actions
-block histamine-2 receptor sites in the parietal cells of the stomach that are responsible for secretion of gastric acid -increase PH of stomach acid
Histamine-2 antagonists indications
-GERD
-short term- peptic ulcer
-prohylaxis (prevention) of stress induced ulcers, GI bleeds, and NSAID ulcers
-relieves symptoms of heartburn and indigestions
-uclers caused by H.pylori
GI disorder drugs: antacids
-interact with acids at the chemical level to neutralize them
-sodium bicarbonate
-calcium salts (oystercal, Tums)
-magnesium salts (milk of magnesia, maalox)
-aluminum salts (amphojel)
antacids indications
-relief of upset stomach due to hyperacidity
-hyperacidity associated with peptic ulcer, gastritis, peptic esophagitis, gastric hyperacidity, hiatal hernia
antacids adverse effects
-hypercalcemia and constipation
-milk-alkali syndrome (calcium)
-hypophosphatemia with aluminum antacids
-rebound acidity
-diarrhea (magnesium)
-fluid retention/heart failure, metabolic alkalois (sodium bicarb)
antacids drug drug
affect absorption of many drugs- separate from other meds by 2 hours at least
treatment of GI: proton pump inhibitors (PPIS)
-suppress the secretion of HCL into the lumen of the stomach
-pantoprazole (protonix), omeprazole, esomeprazole
PPI actions
suppress gastric acid secretion by specificially inhibiting the hydrogen-potassium adenosine triphosphatase enzyme system on the secretory surface of gasric parietal cells
-block the final step of acid production, lowering acid levels in the stomach
PPI indications
-short term treatment of peptic ulcer, gerd, erosive esophogatis, begnign gastric disease
-maintenance therapy for healing erosive esophogitis, and ulcers
-used in combo with amoxicillins and clarithromycin to treat H. pylori infection
PPI adverse effects
-superinfections: CDIFF
-long term usage: hypomagnesemia, and bone loss with decrease calcium (risk for osteoporosis and fractures)
-rebound acid hypersecretions can occur when stopping, therefor short term, low doses should be used
PPI drug drug interactions
-clopidogrel(plavix) avoid in combo PPIs can inferfere with antiplatelet activity
Helicobacter pylori
-clients with peptic ulcers who are postive for the bacteria get treated with antibiotics
-H.pylori is gram neg bacillus
-
h. pylori treatment meds
2 Antibiotics: clarithromycin, amoxicillin, metronidazole, tetracycline
PPI
Bismuth subsalicylate
treatment of GI disorders: GI protectants
-coat any injured area in the stomach to prevent further injury from acid
-sucralfate (carafate)
GI protectants action
-from an ulcer adherent complex at duodenal ulcer sites, protecting the sites against acid, pepsin, and bile salts
-prevents further breakdown and promotes ulcer healing
GI protectants indications
-short term treatment of duodenal ulcers
-maintenance of duodenal ulcers after healing
-treatment of oral and esophogeal ulcers due to radiation, chemotherapy, or sclerotherapy
Treatments of GI disorders: prostaglandins
-inhibit the secretion of gastrin and increase the secretion of the mucous lining of the stomach, providing a buffer
-synthetic prostaglandin E1 analogue: misoprostol (cytotec)
prostaglandins (misoprostol) actions
-inhibits gastric acid secretion and increases bicarbonate and mucous production in the stomach- protects the stomach lining
prostaglandins (misoprostol) indications
-prevention of NSAID induced gastric ulcers in adults who are at high risk
-off label: termination of pregnancy
Prostaglandins (misoprostol) adverse effect
miscarriage
Digestive enzymes
-substances produced in the GI tract to break down foods into usable nutrients
-saliva substitute: aquoral, moi-stir, mouth kote, salivart, etc..
-pancrelipase: creon, prancreaze, pertzye, viokace, zenpep
digestive enzyme actions
-saliva substitutes contain electrolytes and carboxymethylcellulose to act as a thickening agent in dry mouth conditions (make the flood bolus easier to swallow) - clients with stroke, radiation therapy, chemotherapy, sjogren syndrome, etc…
- pancreatic enzymes are replacement enzymes that aid in the digestion and absorption of fats, proteins, and carbohyrdates– clients with cystic fibrosis, pancreatic insufficiency and malabsorption syndromes
-ADMINISTER WITH MEALS AND SNACKS
laxatives: chemical stimulants
-chemically irritate the lining of the GI tract
- bisacodyl (dulcolax), castor oil, senna (senokot)
chemical stimulant laxative actions
begin working at the beginning of the small intestine and increase motility throughout the rest of the GI tract by stimulating the nerve plexus
chemical stimulation laxative indications
short-term treatment of constipation
-prevention of constipation and straining after GI surgery, MI, and obstetrical delivery
-part of a colon preparation prior to elective surgeries or procedures (barium enema, colonoscopy)– used as an adjunct to other agents (such as Go-lytely) to evacuate the colon
chemical stimulant laxative contraindications
acute abdominal disorders: obstruction, appendicitis, diverticulitis, ulceritve colitis
-increased motility could lead to rupture or further exacerbation of the inflammation
chemical stimulant laxative adverse effects
GI: diarerhea, cramping, nausea
CNS: dizziness, headache, weakness
Cathartic dependence
castor oil: blocks absorptions of fats and fat-soluable vitamins and may lead to mal nutrition if used chronically