Respiratory Pharm

Question 1

H1 blockers

Answer 1

Reversible inhibitors of H1 histamine receptors

Question 2

1st generation H1 blockers:

Answer 2

Diphenhydramine, dimenhydrinate, chlorpheniramine

Names contain “-en/-ine” or “-en/-ate”

Question 3

Clinical uses of 1st gen H1 blockers:

Answer 3

Allergy, motion sickness, sleep aid

Question 4

Toxicity of 1st gen H1 blockers:

Answer 4

Sedation, antimuscarinic, anti-alpha-adrenergic

Question 5

2nd generation H1 blockers:

Answer 5

Loratadine, fexofenadine, desloratadine, cetirizine.

Names usually end in “-adine”

Question 6

Clinical uses of 2nd generation H1 blockers:

Answer 6

Allergy

Question 7

Toxicity of 2nd generation H1 blockers

Answer 7

Far less sedating than 1st generation because of decreased entry into CNS

Question 8

Guaifenesin

Answer 8

Expectorant - thins respiratory secretions; does not suppress cough

Question 9

N-acetylcysteine

Answer 9

Mucolytic - can loosen mucus plugs in CF patients. Also used as an antidote for acetaminophen overdose.
Cleaves disulfide bonds within mucus glycoproteins.

Question 10

Dextromethorphan

Answer 10

Antitussive (antagonizes NMDA glutamate receptors).
Synthetic codeine analog.
Mild opioid effect when used in excess.
Mild abuse potential
May cause serotonin syndrome if combined with other serotonergic agents.

Question 11

Drug given for overdose of Dextromethorphan

Answer 11

Naloxone

Question 12

Pseudoephedrine, phenylephrine mechanism:

Answer 12

sympathomimetic alpha-agonistic nonprescription nasal decongestants

Question 13

Pseudoephedrine, phenylephrine clinical use:

Answer 13

Reduce hyperemia, edema and nasal congestion; open obstructed eustachian tubes.
Pseudoephedrine used illicitly to make methamphetamine

Question 14

Pseudoephedrine, phenylephrine toxicity:

Answer 14

Hypertension. Can also cause CNS stimulation/anxiety (pseudoephedrine)

Question 15

Endothelin R Antagonists:

Answer 15

Include Bosentan. Competetively antagonize endothelin-1 R’s. Leads to decreased pulmonary vascular resistance.
Hepatotoxic (monitor LFT’s)

Question 16

PDE-5 Inhibitors:

Answer 16

Include sildenafil. Inhibit cGMP PDE5 and prolong vasodilatory effect of nitric oxide. Also used to treat erectile dysfunction.

Question 17

Prostacyclin analogs:

Answer 17

Include epoprostenol, Iloprost. Prostacyclins (PGI2) w/vasodilatory effects on pulmonary and systemic arterial vascular beds. Inhibits platelet aggregation.
Side effects: flushing, Jaw pain

Question 18

Asthma drugs:

Answer 18

Bronchoconstriction is mediated by 1. inflammatory processes, and 2. parasympathetic tone; therapy is directed at these 2 pathways

Question 19

B2-agonist:

Answer 19

Albuterol, Salmeterol, formoterol

Used in asthmatics

Question 20

Albuterol:

Answer 20

B2-agonist. Relaxes bronchial smooth muscle. Use during acute exacerbation of asthma.

Question 21

Salmeterol, formoterol

Answer 21

Long acting B2 agonists for asthma prophylaxis. Adverse effects are tremor and arrhythmia.

Question 22

Methylxanthines

Answer 22

Theophylline

Question 23

Theophylline

Answer 23

Methylxanthine that likely causes bronchodilation by inhibiting phosphodiesterase (use in asthmatics). Increases cAMP levels, due to decreased cAMP hydrolysis.
Usage is limited by narrow therapeutic index (cardiotoxicity, neurotoxicity, ex. arrhythmias and seizures)
Metabolized by P-450.
Blocks actions of adenosine (a bronchoconstrictor)

Question 24

Muscarinic antagonists:

Answer 24

Ipratropium (Atrovent)

Question 25

Ipratropium

Answer 25

Competitive block of muscarinic receptors, preventing bronchoconstriction (use in asthmatics). Also used for COPD, as is tiotropium, a long acting muscarinic antagonist.
Often used with albuterol.

Question 26

Corticosteroids:

Answer 26

Beclomethasone, fluticasone, Budesonide

Question 27

Beclomethasone, fluticasone, Budesonide:

Answer 27

Inhibit the synthesis of virtually all cytokines. Inactivate NF-KB, transcription factor that induces production of TNF-a and other inflammatory agents. 1st line therapy for chronic asthma (everyday inhaled)

Question 28

Antileukotrienes:

Answer 28

Montelukast, Zafirlukast, Zileuton

Question 29

Montelukast, Zafirlukast

Answer 29

block leukotriene receptors (CysLT1). Especially good for aspirin induced asthma. $$$

Question 30

Zileuton

Answer 30

5-lipoxygenase pathway inhibitor. Blocks conversion of arachidonic acid to leukotrienes. $$
SE: hepatotoxicity

Question 31

Omalizumab

Answer 31

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.

Question 32

Methacholine

Answer 32

Muscarinic receptor agonist. Used in bronchial provocation challenge to help diagnose asthma
Asthmatics have exaggerated response to low doses

Question 33

Bosentan

Answer 33

Used to treat pulmonary arterial hypertension. Competitively antagonizes endothelin-1 receptors, decreasing pulmonary vascular resistance.

Question 34

Cromolyn Sodium:

Answer 34

Mast cell stabilizer - prevents histamine release from mast cells. Only prophylactic use. Largely replaced by leukotriene antagonists (zileuton). $$$

Question 35

Terbutaline

Answer 35

B2 agonist. Bronchodilator (reliever inhaler)

Off label use: oral, stop premature contractions (delay labor 48 hours)

Question 36

Tiotropium:

Answer 36

long acting muscarinic antagonist - often used with albuterol