Respiratory Flashcards
H1 blockers are reversible inhibitors of H1 histamine receptors. There are 1st and 2nd generation drugs. List them. List their clinical uses and toxcities.
1st generation: diphenhydramine, dimenhydrinate, chlorpheniramine
clinical uses: allergy, motion sickness, sleep aid
toxicity: sedation, antimuscarinic, anti-alpha-adrenergic
2nd generation: loratadine, fexofenadine, desloratadine, cetirizine
clinical uses: allergy
toxicity: far less sedating than 1st generation b/c less entry into CNS
Expectorants help bring up mucus and other materials from the lungs, bronchi, and trachea. Compare and contrast the 2 expectorants.
1) Guaifenesin: expectorant that thins respiratory secretions; DOES NOT suppress cough reflex
2) n-acetylcysteine: can loosen mucous plugs in CF pts by disrupting sulfide bonds (also used as an antidote for acetaminophen overdose)
What is dextromethorphan?
It is an antitussive (antagonizes NMDA glutamate receptors). Synthetic codeine analog (has mild opioid effect when used in excess -then use naloxone as antidote). Mild abuse potential
may cause serotonin syndrome if combined w/ other serotonergic agents
How can pseudoephedrine and phenyleprine be used as nasal decongestants? Toxicity?
Pseudoephedrine, phenylephrine are a-adrenergic agonists (vasoconstrict) that can reduce hyperemia, edema, nasal congestion, open obstructed eustachian tubes.
Toxicity: HTN, can also cause CNS stimulation/anxiety (pseudoephedrine which can be illicitly used to make methamphetamine).
3 groups of drugs targeted at treating pulmonary hypertension: 1) endothelin receptor antagonists, 2) PDE-5 inhibitors, 3) prostacyclin analogs. How do the endothelin receptor antagonists work? What will you have to monitor?
Endothelin receptor antagonists (include Bosentan) competitively antagonize endothelin-1 receptors to decrease pulmonary vascular resistance.
Most monitor LFTs b/c of hepatotoxicity.
3 groups of drugs targeted at treating pulmonary hypertension: 1) endothelin receptor antagonists, 2) PDE-5 inhibitors, 3) prostacyclin analogs. How do the PDE-5 inhibtiors work?
PDE-5 inhibitors (include sildenafil) inhibit cGMP PDE5 leading to increase cGMP and prolong vasodilatory effects of NO. Also used to treat erectile dysfunction
3 groups of drugs targeted at treating pulmonary hypertension: 1) endothelin receptor antagonists, 2) PDE-5 inhibitors, 3) prostacyclin analogs. How do the prostacyclin analogs work?
Side effects?
Prostacyclin analogs (include epoprostenol, iloprost) are PGI2 wtih direct vasodilatory effects on pulmonary and systemic arterial vascular beds, can inhibit platelet aggregation.
Side effects: flushing, jaw pain
Asthma drugs are directed at the 1) inflammatory processes and 2) parasympathetic tone that mediate bronchoconstriction causing the asthma. The 3 b2-agonists -which do you use for acute exacerbation? What about for long? List side effects.
- albuterol relaxes bronchial smooth muscle and is used during acute exacerbation (it is short-acting)
- Salmeterol and formoterol are long-acting b2-agonists that are used for asthma ppx. Adverse effects are: tremors and arrhythmia
How are corticosteroids (list 2 specific names) used in the treatment of asthma?
Fluticasone, budesonide inhibit the synthesis of virtually all cytokines by inactivating NF-kB, the tx factor that induces production of TNF-alpha and other inflamm agents. It is the 1st line therapy for chronic asthma. NOT DOC for acute asthma (albuterol is).
What’s the 1st line therapy for chronic asthma?
fluticasone, budesonide (corticosteroids)
List the 2 muscarinic antagonists used in asthma.
- ipratropium -competitively blocks muscarinic receptors, preventing bronchoconstriction. Also used for COPD.
- tiotropium -is long acting
List the 3 antileukotrienes separating them in terms of mech of action. List side effects, and which is espec good for aspirin-induced asthma?
1) montelukast, zafirlukast
- block leukotriene receptors (CysLT1)
- esp. good for aspirin-induced asthma (nasal polyps)
2) zileuton
- 5-lipooxygenase inhibitor will block conversion from arachidonic acid to leukotrienes
- HEPATOTOXIC
What is omalizumab? When is it used?
It is a monoclonal anti-IgE antibody that binds mostly unbound serum IgE and blocks binding to FceRI.
Used in allergic asthma resistant to inhaled steroids (budesonide, fluticasone) and long-acting b2-agonists (salmeterol, formoterol).
Methylxanthines (e.g. Theophylline) are adenosine receptor blockers that cause bronchodilation by inhibiting PDE, increase cAMP due to decreased cAMP hydrolysis. How come usage in asthma is limited?
It has a narrow therapeutic index (cardiotoxicity, neurotoxicity); metabolized by cytochrome p450
Methacholine is used in?
Methacoline is a cholinomimetic (M3 agonist) used in bronchial challenge test to help diagnost asthma. M3 agonist activity includes increase secretions and increase bronchoconstriction.
