Respiratory

Question 1

Antihistamines
First Gen.
Diphenhydramine, Dimenhydrinate, Chlorpheniramine

Answer 1

MOA: Reversible inhibitors of H1 histamine receptors

Use:
Allergy, motion sickness, sleep aid

Adv. effects:
Sedation, antimuscarinic (flushed skin, mydriasis), anti-alpha-adrenergic

Question 2

Antihistamines
Second Gen.
Loratadine, Fexofenadine, Desloratidine, Cetrizine

Answer 2

MOA: Reversible inhibitors of H1 histamine receptors

Use: Allergy

Adv. effects:
Far less sedating than 1st gen because of decreased entry into CNS

Question 3

Guaifenesin

Answer 3

Expectorant - thins respiratory secretions; does not suppress cough reflex.

Question 4

N-acetylcysteine

Answer 4

Mucolytic - liquifies mucus in COPD patients by disrupting disulfide bonds.
Used as an antidote for acetaminophen overdose

Question 5

Dextromethorphan

Answer 5

Antitussive (antagonizes NMDA glutamate receptors)

Synthetic codeine analog

Mild opioid effect (when used in excess)

Overdose treated wuth Naloxone

Mild abuse potential

May cause serotonin syndrome if combined w. other serotonergic agents

Question 6

Pseudoephedrine, Phenylephrine

Answer 6

MOA:
alpha-adrenergic agonists, used as nasal decongestants

Use:
Reduce hyperemia
Edema
Nasal congestion
Open obstructed eustachian tubes
Pseudoephedrine used illicitly to make methamphetamine

Adv. effects:
Hypertension
CNS stimulation/anxiety (pseudoephedrine)

Question 7

Bosentan

Answer 7

MOA:
Competitively antagonizes endothelin-1 receptors –> decreases pulmonary vascular resistance

Use: Pulmonary htn

Adv. effects:
Hepatotoxic (monitor LFTs)

Question 8

Sidenafil

Answer 8

MOA:
Inhibitors cGMP PDE-5 and prolongs vasodilatory effect of nitric oxide

Use:
Pulmonary htn
Erectile dysfunction

Question 9

Epoprostenol, Iloprost

Answer 9

MOA:
PGI2 (prostacyclin) w/ direct vasodilatory effects on pulmonary and systemic arterial vascular beds
Inhibits platelet aggregation

Use: Pulmonary htn

Adv. effects:
Flushing
Jaw pain

Question 10

Albuterol

Answer 10

Short acting Beta2 agonist

Use: Asthma; used during acute exacerbation

Relaxes bronchial smooth muscle

Question 11

Salmeterol, Formoterol

Answer 11

Long acting Beta2 agonist

Use: Asthma prophylaxis

Adv. effects:
tremor
arrhythmia

Question 12

Inhaled corticosteroids

Fluticasone, Budesonide

Answer 12

MOA:
Inhibit synthesis of all cytokines
Inactivate NF-kB (Transcription factor that induces production of TNF-a and other inflammatory agents)

Use:
first line for chronic asthma

Question 13

Ipratropium

Answer 13

MOA: competitively blocks muscarinic receptors, preventing bronchoconstriction

Use: COPD

Question 14

Montelukast, Zafirlukast

Answer 14

Block leukotriene receptors

Good for aspirin induced asthma

Question 15

Zileuton

Answer 15

MOA:
5-lipoxygenase pathway inhibitor
Blocks conversion of arachidonic acid to leukotrienes

Use: Asthma

Adv. effects:
Hepatotoxic

Question 16

Omalizumab

Answer 16

MOA: binds unbound serum IgE and blocks binding to FceRI.

Use: Allergic asthma w/ inc. IgE levels resistant to inhaled steroids and long acting beta2 agonists

Question 17

Theophylline

methylxanthines

Answer 17

MOA:
Causes bronchodilation by inhibiting phosphodiesterase –> increase cAMP levels due to decrease in cAMP hydrolysis

Use: asthma
limited bc of narrow therapuetic index (cardiotoxcitiy, neurotoxicity)

Metabolized by cytochrome P450

Blocks actions of adenosine

Question 18

Methacholine

Answer 18

Muscarinic receptor (M3) agonist

Used in bronchial challenge test to help diagnose asthma