Respiratory Flashcards
H1 antagonists
Reversible inhibitors of H1 histamine receptors
H1 antagonists - 1st generation
Examples
Diphenhydramine
Dimenhydrinate
Chlorpheniramine
“-en/-ine” or “-en/-ate”
Diphenhydramine, Dimenhydrinate, Chlorpheniramine
Uses and toxicity
H1 antagonists - 1st generation
Uses = allergy, MOTION SICKNESS, sleep aid
Toxicity = sedation, antimuscarinic, anti-a-adrenergic
H1 antagonists - 2nd generation
Examples
Loratadine Fexofenadine Desloratadine Cetirizine "-adine"
Loratadine, Fexofenadine, Desloratadine, Cetirizine
Uses and toxicity
H1 antagonists - 2nd generation
Uses = allergy
Toxicity = far LESS SEDATING than 1st gen due to decreased CNS entry
Expectorants (3)
Guaifenesin
N-acetylcysteine
Dextromethorphan
Guaifenesin
Expectorant
Thins respiratory secretions
Does NOT suppress cough reflex
N-acetylcysteine
Mucolytic
Can loosen mucous plugs in CF patients
Also used as antidote for acetaminophen overdose
Which drug can be used for acetaminophen overdose?
N-acetylcysteine
Dextromethorphan
Antitussive NMDA glutamate receptor antagonist Synthetic codeine analog (mild opioid effect when used in excess) Naloxone used in overdose Mild abuse potential
Which drug can be used for dextromethorphan overdose?
Naloxone
Pseudoephedrine, Phenylephrine
MOA
Sympathomimetic a-agonistic nonprescription nasal decongestants
Reduce hyperemeia, edema, and nasal congestion
Open obstructed eustachian tubes
Pseudoephedrine used in illicit methamphetamine production
Sympathomimetic a-agonistic nonprescription nasal decongestants
Toxicity
Pseudoephedrine, Phenylephrine
Hypertension
Can also cause CNS stimulation/anxiety (pseudoephedrine)
Asthma drug therapy targets (2)
Inflammatory processes
Parasympathetic tone
Both lead to bronchoconstriction
B2 agonsts
Albuterol
Salmeterol, formoterol
Albuterol
B2 agonist
Relaxes bronchial smooth muscle (B2)
Use during acute exacerbation
Salmeterol, formoterol
Use? Adverse effects (2)?
B2 agonists
Long acting agents for prophylaxis
Adverse effects are tremor and arrhythmia
Theophylline
Methylxanthines
Likely causes bronchodilation by inhibiting phosphodiesterase = increase cAMP levels due to decreased cAMP hydrolysis
What factor limits theophylline usage? How metabolized? Blocks actions of which other drug?
Narrow therapeutic index = cardiotoxicity, neurotoxicity
Metabolized by cytochrome P450
Blocks actions of adenosine
Ipratropium
Muscarinic antagonist
Competitive block of muscarinic receptors, preventing bronchoconstriction
“I pray I can breathe”
Also used for COPD (as is tiotropium, a long acting version)
Beclomethasone, fluticasone
Corticosteroids
Inhibit synthesis of virtually all cytokines
Inactivate NF-kB (transcription factor that induces production of TNF-a and other inflammatory agents)
First line therapy for chronic asthma
Antileukotrienes
Montelukast
Zafirlukast
Zileuton
Montelukast, zafirlukast
Antileukotrienes
Block leukotriene receptors
Especially good for aspirin-induced asthma
Zileuton
Antileukotriene
5-lipoxygenase pathway inhibitor
Blocks conversion of arachidonic acid to leukotrienes
Omalizumab
Monoclonal anti-IgE antibody
Binds mostly unbound serum IgE and blocks binding to FcERI
Used in allergic asthma resistant to inhaled steroids and long-acting B2-agonists
Methacholine
Muscarinic receptor agonist
Used in bronchial provocation challenge to help diagnose asthma
Bosentan
Used to treat pulmonary arterial hypertension
Competitively antagonizes endothelin-1 receptors, decreasing pulmonary vascular resistance
