Resp Pharm from FA

Question 1

How do H1 blockers work?

Answer 1

Reversible inhibition of H1 histamine receptors

Question 2

Diphenhydramine, dimenhydrinate, chlorpheniramine

Class? Mech? Use? Tox?

Answer 2

First generation H1 blockers

Mech: reversible inihibition of H1 histamine receptors

Use: allergy, motion sickness, sleep aid

Tox: sedation, antimuscarinic, anti-alpha-adrenergic

Notes: names contain “en/ine” or “en/ate”

Question 3

Loratidine, fexofenadine, desloratidine, cetirizine

Class? Mech? Use? Tox?

Answer 3

second generation H1 blockers

Mech: reversible inhibition of H1 histamine receptors

Use: allergies

Tox: far less sedating than 1st generation due to decreased entry into CNS

Note: names usually end in “adine”

Or, “Less Feeling of CEntral DESpression”

Question 4

Guaifenesin

Class? Mech?

Answer 4

Expectorant

Mech: thins respiratory secretions. Does not suppress cough reflex

Question 5

N-acetylcysteine

Class? Mech?

Answer 5

Expectorant

Mucolytic: loosens mucous plugs in CF patients. Also an antidote for acetaminophen OD.

Question 6

Dextromethorphan

Class? Mech?

Answer 6

Antitussive.

Antagonizes NMDA receptors.

Synthetic codeine analog. Mild opioid effect if used in excess. Naloxone can be given for overdose. Mild abuse potential.

Question 7

Pseudoephedrine, Phenylephrine

Class? Mech? Use? Tox?

Answer 7

Class: nasal decongestant (over the counter)

Mech: Sympathomimetic alpha-agonist

Use: reduce hyperemia, edema and nasal congestion. Open obstructed eustacian tubes. (Pseudoephedrine illicitly used to make methamphetamine.)

Tox: HTN. Pseudoephedrine can cause CNS stim/anxiety.

Question 8

General mechanisms of asthma drugs?

Answer 8

Bronchoconstriction mediated in two ways:

1. inflammatory processes
2. parasymphatic tone

so Tx is directed at those pathways.

Question 9

Albuterol

Class? Mech?

Answer 9

Asthma drug, Beta-2 agonist

Mech: Relaxes bronchial smooth muscle (beta2).

Use: acute exacerbation

Question 10

Salmeterol, Formoterol

Class? Mech? Use? SEs?

Answer 10

Asthma drugs, beta-2 agonists

Use: long-acting agents for prophylaxis

SEs: tremor, arrhythmia

Question 11

Theophylline

Class? Mech? Use?

Answer 11

Asthma drug, Methylxanthine

Mech: likely causes bronchodilation by inhibiting phosphodiesterase –> increases cAMP levels due to decreased cAMP hydrolysis.

Use: limited due to narrow therapeutic index.

AE: cardiotoxic, neurotoxic

Metabolized by cytochrome P-450

Blocks actions of adenosine

Question 12

Ipratropium

Class? Mech? Use?

Answer 12

Asthma drug, Muscarinic antagonist

Mech: competitive block of muscarinic receptors, prevents bronchoconstriction.

Use: asthma, COPD

Tiotropium is a long-acting muscarinic antagonist also used for COPD.

Question 13

Beclomethasone, Fluticasone

Class? Mech? Use?

Answer 13

Asthma drugs, Corticosteroids

First line for chronic asthma

Inhibit the synthesis of virtually all cytokines. Inactivates NF-KB (transcription factor that induces production of TNF-alpha and other inflammatory agents).

Question 14

Montelukast, Zafirlukast

Class? Mech? Use?

Answer 14

Asthma drugs, Antileukotrienes

Block leukotriene receptors. Especially good for aspirin-induced asthma.

Question 15

Zileuton

Class? Mech? Use?

Answer 15

Asthma drugs, Antileukotriene

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

Question 16

Omalizumab

Class? Mech? Use?

Answer 16

Asthma drug, monoclonal anti-IgE antibody.

Binds unbound serum IgE, blocks binding to FCeRI.

Used in allergic asthma resistant to inhaied steroids and long-acting B2-agonists.

Question 17

Methacholine

Class? Mech? Use?

Answer 17

Asthma drug

Muscarinic receptor agonist

Used in bronchial provocation challenge to help diagnose asthma

Question 18

Bosentan

Class? Mech? Use?

Answer 18

Asthma drug

Competitively antagonizes endothelin-1 receptors, decreases pulm vascular resistance.

Used for pulmonary artery hypertension.