Respiratory study guide PDF

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Study guide for exam 4...

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RESPIRATORY PHARMACOLOGY Upper respiratory system: nose, mouth, pharynx, larynx, trachea and bronchial tree  Air moves into the nasal cavity through the nose, nasal hairs catch and filter foreign substances, air is warmed by blood vessels in nasal passage o Walls of the nasal cavity are sensitive to irritation, when stimulated a CNS reflex is initiatedsneeze Common conditions: common cold, allergic/seasonal rhinitis, sinusitis, pharyngitis, laryngitis, influenza 4 Classes of drugs for URS: 1 Antitussives 2 Antihistamines 3 Decongestants 4 Expectorants Antitussives:  Dextromethorphan (DM), Delsym, Robitussin, Vicks 44 Cough  Codeine  Hydrocodone, Hycodan, hydromet, mycodone  Benzonate, Tessalon pearls Antihistamines:  First generation o Diphenhydramine (Benadryl) o Chlorpheniramine (Chlortrimeton) o Brompheniramine (Veltane)  Second generation o Fexofenadine (Allegra) o Loratadine (Alavert, Claritin) o Desloratadine (Clarinex) o Cetirizine (Zyrtec) o Azelastine (Astelin) Decongestants:  Pseudoephedrine (PSE)  Phenylephrine, Sudafed PE-oral, Noe-Synephrine-nasal spray  Oxymutazoline (Afrin)  Tetrahydrozoline (Tyzine) Expectorants:  Guafenesin (Robitussin, Mytussin)

Antitussives: cough suppressants Dextromethorphan (DM), Delsym, Robitussin, Vicks 44 Cough I: MOA: directly inhibits cough center in medulla, chemically r/t opiate agonists K: absorbed in GI, metabolized by 2D6, excreted renally C/P: emphysema asthma chronic cough, hepatic impairment, Pregnancy cat. C AE: (rare), n/v, drowsiness, dizziness, irritability, restlessness D-I: increased sedation w/ CNS depressants, MAOI’sserrotonin syndrome, Fluoxetine possible hallucinations, grapefruit & OJ’s E: Codeine (opioid agonist) controlled substance I: MOA: works on medulla, active metabolite morphine-6-glucuronide (prolonged narc effect in RF); more sedation than DM, some resp. depression K: hepatic metabolism, renal excretion C: post-surgical pts, pts that must cough to maintain a patent airway P: Pregnancy/BF, emphysema, asthma AE: sedation, dry mouth, n/v, constipation D-I: E: Hydrocodone, Hycodan, hydromet, mycodone Opioid agonist derivative of codeine, controlled substance I: MOA: medulla; more sedation than codeine, some resp. depression K: hepatic metabolism, renal and bile excretion C: post-surgical pts, pts that must cough to maintain a patent airway P: Pregnancy/BF, emphysema, asthma AE: sedation, dry mouth, n/v, constipation D-I: E: Benzonate, Tessalon pearls-(when used as an anesthetic reduces irritability) Non-narc I: MOA: exact MOA unknown; anesthetizes the stretch R in the resp. tract, lung tissue and pleura which interferes w/ activity and decreases cough reflex pearls can be applied topically before MRI, they show up as markers to aid in mapping K: C/P: AE: D-I: E:

Decongestants: mucolytics, reduces volume of nasal mucus Pseudoephedrine (PSE) Most common Sudafed I: combat methamphetamine abuse actbehind the counter, amount restricted MOA: reduces volume of nasal mucus: mimics sympathetic stimulation, inhibits catecholamine storage, ST increase of release of catecholamines from synaptic terminal but LT depletion d/t inhibiting storage of catecholamines (drying effect) vasoconstriction in mucous membranes increases cardio, constriction of renal arteriole, anxiety K: absorbed in GI, hepatic metabolism, renal excretion, crosses placental barrier/breast milk C/P: AE: (occur almost immediately) [mild]: tension, anxiety, restlessness, tremor, insomnia [severe]: hallucinations, delusions, convulsions, tachycardia, HTN, arrhythmias [allergic]: skin rash, urticarial D-I: MAOI, guanethidine, methyldopaincreased HTN; any urinary alkalizer like potassium citrate, sodium citrate will increase [C] of PSE d/t tubular reabsorption E: Phenylephrine, Sudafed PE-oral, Noe-Synephrine-nasal spray I: MOA: selectively activates alpha 1 adrenergic Rlittle or no direct action on the heart, increases vascular smooth muscle (vasoconstriction) K: nasal sprays have minimal systemic absorption C: narrow-angle glaucoma, severe HTN AE: [oral]: arrhythmia, HTN, HA, insomnia; [oral and nasal]: rebound nasal congestion Discontinue sprays after 3 days D-I: E: Topical Decongestants: Oxymutazoline (Afrin) & Tetrahydrozoline (Tyzine) I: vasoconstriction MOA: selectively activates alpha 1 adrenergic Rlittle or no direct action on the heart, increases vascular smooth muscle (vasoconstriction) K: C/P: AE: D-I: E:

Antihistamines: mainly used for allergy relief, blocks histamine triggered by inflammation Histamine: major mediator of immune and inflammatory Response; role in IgE-mediated allergic rxnallergen-induced mast cell degranulation rqrs 2 exposures  1st exposure: activates immune responseB-lymphocytes to secrete allergen specific IgE antibodies that bind to R on mast cells thereby sensitizing them  2nd exposure: sensitized mast cells degranulate and local histamine releaseinflam resp Anaphylaxis: mast cell degranulation that is systemic, typically individual previously sensitized by hypersensitivity rxn; systemic distribution of allergenhistamine released throughout the body; results in: systemic vasodilation, hypotension, bronchoconstriction, epiglottal swelling First generation-more sedating (non-selective) Ethanolamines: Diphenhydramine (Benadryl) I: MOA: anticholinergic activity, greatest sedation K: well absorbed, hepatic metabolism C: decreased alertness and motor skills is additive with ETOH and depressant use E: Ethylenediamines and Piperidines: similar to Benadryl Alkylamines: Chlorpheniramine (ChlorTrimeton) I: MOA: modest anticholinergiclow sedation C: decreased alertness and motor skills is additive with ETOH and depressant use E: Phenothiazines: Promethazine (Phergan) I: MOA: high sedation, anticholinergic C: decreased alertness and motor skills is additive with ETOH and depressant use E: Tricyclics: Cyproheptadine (Periactin) I: MOA: low sedation, low anticholinergic, also antagonist at serotonin R C: decreased alertness and motor skills is additive with ETOH and depressant use E: Piperazines: Meclizine (Antivert) I: anti-motion sickness MOA: C: decreased alertness and motor skills is additive with ETOH and depressant use E: 1st generation AE’s: sedation, dry mouth, n/v, urinary retention, dysuria, can develop tolerance

Second generation-less sedating (peripherally selective) more lipophilic and ionized Piperazines: Cetirizine (Zyrtec) I: pet dander (cats) MOA: less sedating C: E: Alkylamines: Acrivastine I: MOA: C: E: Phthalazinones: Azelastine (Astelin) nasal spray I: MOA: local antagonist of histamine at H1 R, does not bind or inactivate histamine C: Pregnancy Cat. C, children older than 5 AE: drowsiness, dizziness, epistaxis, nasal burning, sneezing, dry mouth, bitter taste E: Piperadines: Fexofenadine (Allegra), Loratadine (Claritin) I: anticholinergic and antipruritic effects MOA: selectively blocks histamine at H-R sites; K: hepatic metabolism, 11% renal secretion unchanged, 80% bile excretion AE: viral infection, n/v, dysmenorrhea, drowsiness, dyspepsia, fatigue, QT interval prolongation C: D-I: apple, grapefruit and OJ decrease absorption (3A4); rifampimreduces absorption, St. John’s wortinduces metabolism E: Seldane, Hismanal-pulled from the market b/c they blocked cardiac K+ channel for repolarization which prolonged QT interval Expectorants: liquefy mucus Guafenesin (Robitussin, Mytussin) I: MOA: works to liquefy LRT secretions, decreases viscosity and makes it easier to cough up, makes cough more productive, improves airflow K: absorbed from GI tract AE: n/v, anorexia, HA, dizziness, rash C: Pregnancy cat. C D-I: no major E:

Lower respiratory system: sterile d/t mechanisms in URS  Protective mechanisms: tubes in lower airway contain goblet cells that secrete mucus to entrap particlesMicroorganisms and other foreign bodies are removed from the air by cilia  Gas exchange, perfusion and respiration: lung tissue receives blood supply from bronchial artery that branches off the thoracic aorta  Ventilation: act of breathing controlled by the CNS Common conditions: acute bronchitis, asthma, chronic airway limitation, chronic bronchitis, emphysema, PNA, Cystic Fibrosis Classes of drugs for LRS: 1 Mucolytics 2 Bronchodilators a. Beta 2 Agonists (short acting and long acting) b. Anticholinergics c. Xanthine Derivatives 3 Anti-inflammatory Agents Mucolytics:  Acetylcysteine (Mucomyst) Bronchodilators  Beta 2 Agonists: o Short acting: Bitolterol, Isoetharine, Metaproterenol, Pirbuterol, Isoproterenol, Epinephrine o Long acting: Albuterol, Terbutaline, Formoterol, Salmeterol, Arformoterol (Brovana) o Combo/LABA’s: Symbicort (Budesonide/formoterol), Advair (Fluticasone/ salmeterol), Dulera (Mometasone/formoterol) o Levalbuterol (Xopenex)  Anticholinergics o Ipratroprium (+ albuterol as Combivent) o Tiotropium (Spiriva)  Xanthine derivatives o Methylxanthines: Theophylline Anti-inflammatory agents  Inhaled corticosteroids: Fluticasone > Budesonide > Beclomethasone > Flunisolide = Trimcinolone  Leukotriene Antagonists: Zafirlukast (Accolate), Montelukast (Singulaire); Zileuton  Cromolyn (Intal), Nedocromil (Tilade)

Mucolytics: liquefy thick secretions Acetylcysteine (Mucomyst) I: CF, PNA, TB, atelectasis; can be used to clear the airway for bronchoscopy, tx for acetaminophen overdose, preventative for contrast-induced renal complications in high risk pts MOA: liquefy thick secretions; splits disulfide bonds that hold mucus material togetherdecreases viscosity and tenacity of mucus; protects liver cells from acetaminophen toxicity, acts as an antioxidant reducing unbound radicals in contrast-induced nephrotoxicity K: nebulizer/direct instillation; hepatic metabolism, renal excretion AE: bronchospasm, rhinorrhea, fever, chills, drowsiness, clammy skin, angioedema, rash, hypotension and tachycardia C: respiratory compromised pts, P: asthma, severe hepatic disease (d/t increased acetylcysteine), Pregnancy cat. B E: Anti-inflammatory Agents: asthma controllers, decrease airway inflammation Inhaled corticosteroids: Fluticasone > Budesonide > Beclomethasone > Flunisolide = Trimcinolone I: anti-inflammatory to decrease hyperresponsiveness to triggers K: aerosol use preferred: MDI + spacer, dry powder, budesonide respules for nebulizers LT daily prevention of s/s w/ inhaled drugs PO for acute s/s AE: dysphonia, cough, oral thrush, [adrenal axis suppression] magnified by PO steroids chronically; cataracts, increased ocular [P] (esp. in elderly, when drug is misapplied near eyes or used mos-years); growth velocity reduced by 1cm/yr; decreased bone mineral density (esp. in the elderly, post-menopausal women/men) Leukotriene Antagonists Zafirlukast (Accolate), Montelukast (Singulaire)-LT4 R antagonist Zileuton-5 Lipoxygenase Inhibitor I: controller in mild, persistent asthma PO alternative, or add on controller to inhaled corticosteroid use, allergic rhinitis and mild asthma, no effect on congestion MOA: C: D-I: E: Cromolyn (Intal), Nedocromil (Tilade) I: pre-allergen or pre-exercise, mild chronic persistent asthma only, nasal cromolyn for mild allergic rhinitis MOA: inhibits mast cell degranulation to block release of inflammatory compounds AE: bronchospasm, coughing C: D-I: E:

Bronchodilators: asthma relievers, alleviate smooth muscle bronchoconstriction Beta 2 “selective” Agonists (short acting and long acting) Short acting (SABA’s): Bitolterol, Isoetharine, Metaproterenol, Pirbuterol, Isoproterenol, Epinephrine Long acting (LABA’s): Albuterol, Terbutaline, Formoterol (w/ Budesonide as Symbicort), Salmeterol (Serevent; w/ Fluticasone as Advair), Arformoterol (Brovana) I: MOA: stimulate R to activate adenyl cyclase to produce cAMPincreases intracellular calcium to produce skeletal muscle relaxation, mast cells stabilization, skeletal muscele stimulation tolerance (tachyphylaxis) d/t down regulation and altered R binding, decreased duration of bronchodilation w/ round the clock use K: inhalation preferred w/ increased dose rqrmts in acute disease AE: [constitutional]: tremor, jitters, n, HA; [tolerance], CV: arrhythmias, reflex tachycardia; hyperglycemia, hypokalemia C: D-I: avoid beta 1 or alpha acting drugs when possible for AE (epinephrine, metaproterenol; potentiates the effect of pressors, sympathomimetics, anesthetics, ergots E: Levalbuterol (Xopenex) I: MOA: pure isomer, not approved for acute disease K: nebulizer form, HFA MDI available AE: C: D-I: E: LABA AE: nocturnal asthmaadd to aerosol steroids to avoid dose escalation in chronic asthma; can be used w/ albuterol, exercise-induced bronchospasm-when exercise is prolonged Combo steroid/LABA: Symbicort (Budesonide/formoterol), Advair (Fluticasone/salmeterol), Dulera (Mometasone/formoterol) New for COPD: Breo Ellipta (Fluticasone/vilanterol)-no indication for asthma Roflumilast (Daliresp)-potential mental health problems rqrs guide to inform pts of changes in mood, thinking, behavior, wt. loss

Anticholinergics I: asthma MOA: competitive inhibitors of cholinergic R, less bronchodilation w/ slower onset when compared to Beta 2 agonists K: MDI’s, nebulization AE: mild dry mouth, constipation, tachycardia, blurred vision, glaucoma, urinary retention-rare C: narrow-angle glaucoma, prostatic hyperplasia, bladder obstruction Ipratroprium (+ albuterol as Combivent) I: MOA: K: AE: C: D-I: E: Tiotropium (Spiriva) I: bronchodilator (asthma)-long acting anticholinergic, COPD MOA: AE: dry mouth (increases w/ age), constipation, increased HR, blurred vision, glaucoma, urinary difficulty K: more effective than ipratropium C: D-I: E: Xanthine Derivatives Methylxanthines: Theophylline I: MOA: phosphodiesterase inhibition to increase cAMP for: bronchodilation, enhanced, diaphragmatic contractility, stimulates the respiratory center (apnea of prematurity) K: well absorbed, hepatic metabolism CYP450 1A2 and 3A3; saturation or zero order kinetics AE: (dose independent) caffeine effects= n, jitters, tremor, HA; [toxicity]: n, emesis, dizziness, arrhythmias, seizures; hyperactivity, lowered seizure threshold, exacerbates GERD C: D-I: erythromycin/clarithromycin, allopurinol, quinolones can all reduce metabolism, along with fever, systemic viral illness or disease states like CHF, or cirrhosis; nicotine increases metabolism E:...