Respiratory Medications PDF

R E S P I R AT O RY M E D I C AT I O N S Antihistamines, Decongestants, Antitussives and Expectorants. U N D E R S TA N D I N G THE COMMON COLD C O P Y R © E L S E I N C . R I R E S E R • Most caused by viral infection (rhinovirus or influenza virus) • Virus invades tissues (mucosa) of upper res...

R E S P I R AT O RY M E D I C AT I O N S Antihistamines, Decongestants, Antitussives and Expectorants. U N D E R S TA N D I N G THE COMMON COLD C O P Y R © E L S E I N C . R I R E S E R • Most caused by viral infection (rhinovirus or influenza virus) • Virus invades tissues (mucosa) of upper respiratory tract, causing upper respiratory infection (URI) • Excessive mucus production results from the inflammatory response to this invasion. • Fluid drips down the pharynx into the esophagus and lower respiratory tract, causing cold symptoms: sore throat, coughing, upset stomach. • Irritation of nasal mucosa often triggers the sneeze reflex. • Mucosal irritation also causes release of several inflammatory and vasoactive substances, dilating small 2 blood vessels in the nasal sinuses and causing nasal T R E AT M E N T O F THE COMMON COLD • Involves combined use of antihistamines, nasal decongestants, antitussives, and expectorants • Treatment is symptomatic only, not curative. Loading… • Symptomatic treatment does not eliminate the causative pathogen. • Difficult to identify whether cause is viral or bacterial • Treatment is “empiric therapy,” treating the most likely cause • Antivirals and antibiotics may be used, but a definite viral or bacterial cause may not be easily identified. 3 P E D I AT R I C CONCERNS • In 2008, the U.S. Food and Drug Administration (FDA) issued recommendations that over-the-counter (OTC) cough and cold products not be given to children younger than 2 years of age. • Over sedation, seizures, tachycardia, and even death in toddlers • Evidence shows that such medications are simply not effective in small children • Parents are advised to consult their children’s pediatricians on the best ways to manage these illnesses. • A 2010 study showed a dramatic decrease in young children’s emergency department visits since the 2008 FDA recommendation. 4 ANAPHYLAXIS: SEVERE ALLERGIC REACTIONS H I S TA M I N E • Major inflammatory mediator in many allergic disorders • Allergic rhinitis (e.g., hay fever and mold, dust allergies) • Anaphylaxis • • Release of excessive amounts of histamine can lead to: • Constriction of smooth muscle, especially in the stomach and lungs Angioedema • Increase in body secretions • Drug fevers • • Insect bite reactions • Urticaria (itching) Vasodilatation and increased capillary permeability, movement of fluid out of the blood vessels and into the tissues, and drop in blood pressure and Loading… 5 A N T I H I S TA M I N E S • Drugs that directly compete with histamine for specific receptor sites • Two histamine receptors H1 (histamine 1) H2 (histamine 2) C O P Y R © E L S E I N C . R I R E S E R 6 A N T I H I S TA M I N E S A N D H I S TA M I N E A N TA G O N I S T S 7 H1 antagonists (also called H1 blockers) •Examples: chlorpheniramine, fexofenadine (Allegra), loratadine (Claritin), cetirizine (Zyrtec), diphenhydramine (Benadryl) Antihistamines have several properties •Antihistaminic •Anticholinergic •Sedative H2 blockers or H2 antagonists •Used to reduce gastric acid in peptic ulcer disease •Examples: cimetidine (Tagamet), ranitidine (Zantac), famotidine (Pepcid), nizatidine (Axid) A N T I H I S TA M I N E S : MECHANISM OF ACTION • The binding of H1 blockers to the histamine receptors prevents the adverse consequences of histamine stimulation. • • • Vasodilation Increased gastrointestinal (GI) and respiratory secretions Increased capillary permeability • More effective in preventing the actions of histamine rather than reversing them • Should be given early in treatment before 8 H I S TA M I N E V E R S U S A N T I H I S TA M I N E E F F E C T S Cardiovascular (small blood vessels) Smooth muscle (on exocrine glands) Histamine effects • Dilation and increased permeability (allowing substances to leak into tissues) Antihistamine effects Histamine effects • Stimulate salivary, gastric, lacrimal, and bronchial secretions Antihistamine effects • Reduce salivary, gastric, lacrimal, and bronchial secretions 9 • Reduce dilation of blood A N T I H I S TA M I N E S : OTHER EFFECTS • Skin: reduce capillary permeability, wheal-andflare formation, itching • Anticholinergic: drying effect that reduces nasal, salivary, and lacrimal gland secretions (runny nose, tearing, and itching eyes) • Sedative: some 10 antihistamines cause A N T I H I S TA M I N E S : I N D I C AT I O N S • Management of: • Nasal allergies • Seasonal or perennial allergic rhinitis (hay fever) Loading… • Allergic reactions • Motion sickness • Parkinson’s disease • Sleep disorders • Also used to relieve symptoms associated with the common cold • Sneezing, runny nose • Palliative treatment; not curative 11 A N T I H I S TA M I N E S : C O N T R A I N D I C AT I O N S • Known drug allergy • Narrow-angle glaucoma • Cardiac disease, hypertension • Kidney disease • Bronchial asthma, chronic obstructive pulmonary disease (COPD) • Sole drug therapy during acute asthmatic attacks Albuterol or epinephrine • Peptic ulcer disease • Seizure disorders • Benign prostatic hyperplasia (BPH) Adverse Effects Anticholinergic (drying) effects: most common 12 • Dry mouth • Difficulty urinating • Constipation • Changes in vision Drowsiness • Mild drowsiness to deep • Pregnancy A N T I H I S TA M I N E S : T W O T Y P E S • Traditional: brompheniramine, chlorpheniramine, dimenhydrinate, diphenhydramine, meclizine, and promethazine • Nonsedating: loratadine, cetirizine, and fexofenadine 13 A N T I H I S TA M I N E S : N U R S I N G I M P L I C AT I O N S • Gather data about the condition or allergic reaction that required treatment; also assess for drug allergies. • Instruct patients to report excessive sedation, confusion, or hypotension. • Contraindicated in the presence of acute asthma attacks and lower respiratory diseases, such as pneumonia • Instruct patients to avoid driving or operating heavy machinery; advise against consuming alcohol or other CNS depressants. • Use with caution in patients with increased intraocular pressure, • Instruct patients not to take these medications with other 14 cardiac or renal disease, prescribed or OTC medications D E C O N G E S TA N T S • Two Dosage forms: D E C O N G E S TA N T S : T Y P E• S •Three main types are used: Adrenergics • Oral Inhaled or topically applied to the nasal membranes • Largest group • Sympathomimetics Anticholinergics • Less commonly used • Parasympatholytics Corticosteroids • Topical, intranasal steroids 16 ORAL DECONGESTANTS TOPICAL NASAL DECONGESTANTS Topical adrenergics • Prolonged decongestant effects but delayed onset • • Effect less potent than topical • • • No rebound congestion • Exclusively adrenergics • Example: pseudoephedrine (Sudafed) • Prompt onset Potent Sustained use over several days causes rebound congestion, making the condition worse. Ephedrine, oxymetazoline, phenylephrine, and tetrahydrozoline INHALED INTRANASAL STEROIDS AND ANTICHOLINERGIC DRUGS • Not associated with rebound congestion • Often used prophylactically to prevent nasal congestion in patients with chronic upper respiratory tract symptoms 17 D E C O N G E S TA N T S : N A S A L D E C O N G E S T A N TM S :E C H A N I S M O F I N D I C AT I O N S ACTION • Relief of nasal congestion associated with: Acute or chronic rhinitis Common cold Sinusitis Hay fever Other allergies • May also be used to reduce swelling of the nasal passage and facilitate visualization of the • Site of action: blood vessels surrounding nasal sinuses • Adrenergics Constrict small blood vessels that supply upper respiratory tract structures As a result, these tissues shrink, and nasal secretions in the swollen mucous membranes are better able to drain. • Nasal steroids 18 nasal or pharyngeal membranes Antiinflammatory effect N A S A L D E C O N G E S TA N T S : C O N T R A I N D I C AT I O N S • Drug allergy • Narrow-angle glaucoma • Uncontrolled cardiovascular disease, hypertension • Diabetes and hyperthyroidism • History of cerebrovascular accident or transient ischemic attacks • Long-standing asthma • BPH • Diabetes 19 N A S A L D E C O N G E S TA N T S : A D V E R S E EFFECTS Adrenergics Steroids • Nervousness • Local mucosal dryness • Insomnia • Irritation C O P Y R © E L S E I N C . R I R E S E R 20 • Palpitations • Tremors (Systemic effects caused by adrenergic stimulation of the heart, blood vessels, and CNS) COUGH PHYSIOLOGY • Respiratory secretions and foreign objects are naturally removed by the cough reflex. • Induces coughing and expectoration • Initiated by irritation of sensory receptors in the respiratory tract TWO BASIC TYPES OF COUGH • Productive cough: congested; removes excessive secretions • Nonproductive cough: dry cough 21 ANTITUSSIVES ANTITUSSIVES • Drugs used to stop or reduce coughing • Opioid and nonopioid • Used only for nonproductive coughs! • May be used in cases when coughing is harmful 23 ANTITUSSIVES: MECHANISM OF ACTION • Opioids Suppress the cough reflex by direct action on the cough center in the medulla Analgesia, drying effect on the mucosa of the respiratory tract, increased viscosity of respiratory secretions, reduction of runny nose and postnasal drip Examples • Nonopioids Dextromethorphan: works in the same way ➢ Not an opioid ➢ No analgesic properties ➢ No CNS depression ➢ Benzonatate ➢ Suppress the cough reflex by numbing the stretch receptors in the respiratory tract and prevent reflex stimulation of the medullary cough center ➢ 24 ANTITUSSIVES: ADVERSE EFFECTS • Benzonatate Dizziness, headache, sedation, nausea, and others • Dextromethorphan Dizziness, drowsiness, nausea Contraindications • • • • Opioids Sedation, nausea, vomiting, lightheadedness, constipation • Drug allergy Opioid dependency Respiratory depression Others 25 ANTITUSSIVES: NURSING I M P L I C AT I O N S • Perform respiratory and cough assessment and assess for allergies. • Instruct patients to avoid driving or operating heavy equipment because of possible sedation, drowsiness, or dizziness. • Report any of the following symptoms to the caregiver: Cough that lasts more than 1 week Persistent headache Fever Rash • Antitussive drugs are for nonproductive coughs. 26 • Monitor for intended therapeutic effects. EXPECTORANTS EXPECTORANTS • Drugs that aid in the expectoration (removal) of mucus • Reduce the viscosity of secretions • Disintegrate and thin secretions 28 Example: guaifenesin EXPECTORANTS: MECHANISMS OF ACTION • Reflex stimulation Drug causes irritation of the GI tract. Loosening and thinning of respiratory tract secretions occur in response to this irritation. • Direct stimulation Loading… The secretory glands are stimulated directly to increase their production of respiratory tract fluids. • Final result: thinner mucus that is easier to remove • By loosening and thinning sputum and bronchial secretions, the tendency to cough is indirectly diminished. 29 E X P E C T O R A N T S : I N D I C AT I O N S • Used for the relief of productive coughs associated with: Common cold Bronchitis Laryngitis Pharyngitis Coughs caused by chronic paranasal sinusitis Pertussis Influenza Measles 30 EXPECTORANTS: N U R S I N G I M P L I C AT I O N S • Expectorants should be used with caution in older adults and patients with asthma or respiratory insufficiency. • Patients taking expectorants should receive more fluids, if permitted, to help loosen and liquefy secretions. • Report a fever, cough, or other symptoms lasting longer than 1 week. • Monitor for intended therapeutic effects. 31 QUESTION #1 The common cold is treated with empiric therapy. How can the nurse interpret this meaning? Broad/Wide range - -Symptoms A. O B. , not curing Medications cure the cold. Medications only treat the symptoms. C. Herbal medications are useful to eliminate symptoms. D. Prevention with careful use of medications 32 ANSWER TO SYSTEM QUESTION #1 ANS: B There is no cure for the common cold, and the efficacy of herbal products is not proven. Treatment rendered can only treat the presenting clinical symptoms. 33 QUESTION #2 Before administering an antihistamine to a patient, it is most important for the nurse to assess the patient for a history of which condition? 34 A. Chronic urticaria B. Motion sickness C. Urinary retention D. Insomnia ANSWER TO SYSTEM QUESTION #2 ANS: C The anticholinergic effects of antihistamines may cause difficulty urinating. The other answers are potential indications for an antihistamine. 35 QUESTION #3 Before administering an adrenergic decongestant, it is most important for the nurse to assess the patient for a history of which condition? 36 A. Cataracts B. Gastric ulcer C. Diabetes mellitus D. Hypothyroidism ANSWER TO SYSTEM QUESTION #3 ANS: C Adrenergic drugs are contraindicated in patients with narrow-angle glaucoma, uncontrolled cardiovascular disease, hypertension, diabetes, and hyperthyroidism. They are also contraindicated when the patient is unable to close his or her eyes (e.g., after a cerebrovascular accident), as well as in patients with a history of cerebrovascular accident or transient ischemic attacks, long-standing asthma, BPH, or diabetes. 37 QUESTION #4 A 94-year-old patient has a severe dry cough. He has coughed so hard that the muscles in his chest are hurting. He is unsteady on his feet and slightly confused. Which drug would be the best choice for this patient’s cough? A. Benzonatate (Tessalon Perles) capsules B. Dextromethorphan (Robitussin-DM) oral solution C. Codeine cough syrup D. Guaifenesin (Mucinex) 38 ANSWER TO SYSTEM QUESTION #4 ANS: B 39 Dextromethorphan does not cause respiratory or CNS depression, and it is not an opioid. Guaifenesin is an expectorant that is used to thin excessive mucus, which this patient does not have. QUESTION #5 A patient with a tracheostomy developed pneumonia. It is very difficult for the patient to cough up the thick, dry secretions he has developed. The nurse identifies which drug as being most effective in helping this patient? 40 A. Benzonatate (Tessalon Perles) capsules B. Dextromethorphan (Robitussin-DM) oral solution C. Codeine cough syrup D. Guaifenesin (Mucinex) ANSWER TO SYSTEM QUESTION #5 ANS: D Expectorants such as guaifenesin aid in the expectoration (i.e., coughing up and spitting out) of excessive mucus that has accumulated in the respiratory tract by breaking down and thinning out the secretions. 41 how · close dear rose cough · medulla Most - - Common 1st Gen Antihist mine effect Drowsiness What · Oral Mucenex no rebound -> expectorant Drink Water Ghalfenesin ↑ Fluid thins out Mucous PT W/ - G a expectorant How long 3-5 to fluid , Don't , effect palpatations taking Antihist drive of Dextro ... Robatus in Drowsiness Benadryl R adverse effects Ot takes this what Month C , P , , Drowsiness Spit , , Snit Urinary Retention . Rir Mucanex use Nasal days · Dry thick Mucous - pr that is decongest What is Diphahydrmine O - · to tell Adverse - w/ topical Most concered about ofood . Whats Diff Oral/nasal decon · Systemic effics What Spray - is herbal supplement Echinacea -> Immune Booster Flonase is effective but will take up to 3 weeks before getting max effect (nasal spray) How to take a med (dose) avlible in.. how much to give