NR 566 WEEK 2 STUDY OUTLINE. LATEST 2020/21

NR 566 WEEK 2 STUDY OUTLINE. LATEST 2020/21.NR566 Week 2 Study Outline Many questions are written to assess your clinical application of the material from the textbook, in real-world scenarios. Chapter 17: Drugs Affectin ...

NR 566 WEEK 2 STUDY OUTLINE. LATEST 2020/21.NR566 Week 2 Study Outline Many questions are written to assess your clinical application of the material from the textbook, in real-world scenarios. Chapter 17: Drugs Affecting the Respiratory System • Know the pharmacodynamics, pharmacotherapeutics clinical use, drug interactions and adverse drug reactions for: o o Short and long acting beta agonists Short-acting beta agonists , Albuterol (ProAir, Ventolin, Proventil) , Metaproterenol (Alupent) Terbutaline (Brethine, Brethaire) Bitolterol (Tornalate) Pirbuterol (Maxair ) Levalbuterol (Xopenex) Long-acting beta agonists Salmeterol (Serevent) Formoterol (Foradil) Indacaterol (Arcapta Neohaler) o Arformoterol (Brovana) Pharmacodynamics Albuterol o Selective beta2 agonist with minor beta1 activity o Levalbuterol is where the (S)-isomer from racemic albuterol is removed Salmeterol o Salmeterol is more selective for beta2 receptors than albuterol and has minor beta1 activity. o 12 hour half-life Pharmacokinetics o Precautions and Contraindications: cardiac arrhythmias o Diabetics: potential drug-induced hyperglycemia o Long-acting beta agonists o Black Box warning: The risks of salmeterol (Serevent) and formoterol (Foradil) outweighed the benefits and should not be used singly in asthma for all ages o Two-fold increase in catastrophic events (asthma-related intubations and death) o Terbutaline pregnancy category B (others category C) o Children o Albuterol safe for all age children o Salmeterol should not be used in children less than age 4 years and never singly. Drug and Food Interactions Beta Agonists: Drug Interactions o Digitalis glycosides: increased risk of dysrhythmia o Beta adrenergic blocking agents: direct competition for beta sites resulting in mutual inhibition of therapeutic effects o Including beta blocker eye drops o Tricyclic antidepressants and monoamine oxidase inhibitors potentiate effects of beta agonist on vascular system ADR Beta Agonists: Adverse Drug Reactions o Usually transient o Tachycardia and palpitations o Some central nervous system (CNS) excitation effects o Tremors, dizziness, shakiness, nervousness, and restlessness o Headaches o Salmeterol has an increased risk of exacerbation of severe asthma symptoms if the patient is deteriorating Clinical Use and Dosing Beta Agonists: Clinical Use o Bronchodilators are used primarily in the treatment of bronchospasm associated with asthma, bronchitis (acute or chronic), and chronic obstructive pulmonary disease (COPD) o Albuterol metered dose inhaler (MDI) dose is 2 puffs every 4 to 6 hours o Via nebulizer dose is 2.5 mg/dose o Dose may be repeated twice after 5 to 10 minutes o May combine with ipratropium o Levalbuterol via nebulizer every 6 to 8 hours o Salmeterol DISKUS: 1 puff twice a day o Do not use alone for persistent asthma, combine with an inhaled corticosteroid o Exercise-induced bronchospasm (EIB) o Albuterol: 2 puffs 15 minutes before exercise o Salmeterol: 2 puffs 30 to 60 minutes before exercise o Do not use if already on daily dose of salmeterol o Leukotriene modifiers taken daily may decrease EIB symptoms in 50% of patients, but patient will still need to use albuterol before exercise • o Inhaled anticholinergics o o Xanthine derivatives
: Theophylline and caffeine, Ipratropium bromide (Atrovent) ,Tiotropium bromide (Spiriva) Pharmacodynamics Theophylline and caffeine pharmacodynamics o Bronchial smooth muscle relaxation CNS stimulants Cardiovascular effects Increased gastric acid production Stimulate skeletal muscle o Increased renal blood flow and glomerular filtration rate Pharmacokinetics o o Absorbed rapidly and completely from gastrointestinal (GI) tract o Distributed widely o Volume of distribution altered in: premature neonates, elderly patients, cirrhosis, pregnant women (third trimester), and critically ill patients, probably because of altered protein-binding o Metabolized extensively in liver via CYP 450 into caffeine o Disease states and CYP inducers can influence metabolism of theophylline o Eliminated via the renal system Theophylline: Drug and Food Interactions o Many drug interactions due to metabolism via CYP 450 isoenzyme CYP 1A2, CYP 2E1, and CYP 3A3/4 o Smoking tobacco increases clearance o Benzodiazepines are antagonized by theophylline o Beta agonists may cause additive toxicity