pulmonary drugs

Question 1

List first generation antihistamines

Answer 1

Diphenhydramine/Chlorpheniramine/Brompheniramine, Meclizine/Dimenhydrinate

Question 2

List second generation antihistamines

Answer 2

Loratadine/Fexofenadine/Cetirizine

Question 3

First generation antihistamine MOA

Answer 3

Reversible and competitive blocking of H1 receptors (no H2). Also block muscarinic receptors which leads to sedation (CNS), prevention of nausea and vomiting (CNS), and blocking secretions (ANS). Also blocks sodium channels for local anesthetic action (diphenhydramine) and blocks adrenergic receptors

Question 4

Second generation antihistamine MOA

Answer 4

Blocks H1 receptor almost exclusively. Slight level of sedation possible, but do not penetrate CNS well.

Question 5

Antihistamine pharmacokinetics

Answer 5

All: oral, rapid absorption, Metabolized by liver. First gen: duration of 4-8 hrs. Second gen: longer duration with metabolic and/or renal elimination. Fexofenadine lasts 12 hrs. Loratadine and cetirizine last 24 hrs

Question 6

Clinical uses of antihistamines

Answer 6

allergic rhinitis or other allergic rxns via H1 block. Reduces sneezing, pruritus, rhinorrhea, and some congestion, but not inflammation. Also used for cough suppression via Na channel block, motion sickness (H1 and muscarinic block), nausea (H1 and muscarinic block) and sleep aid (H1 and muscarinic block)

Question 7

Side effects of antihistamines

Answer 7

Sedation (mainly 1st gen), dry mouth (antimuscarinic actions), postural hypotension, GI upset

Question 8

List topical decongestants

Answer 8

Phenylephrine, oxymetazoline

Question 9

list oral decongestants

Answer 9

Pseudoephedrine, phenylephrine

Question 10

Topical decongestants MOA

Answer 10

Stimulate α1-adrenergic receptors of vascular smooth muscle resulting in constriction of nasal blood vessels dilated by histamine or inflammatory response. Promotes drainage, improves breathing via decrease in congestion

Question 11

Oral decongestants MOA

Answer 11

delivers drug via systemic circulation to nasal vascular bed, NOT associated with rebound congestion. Stimulates Stimulate α1-adrenergic receptors of vascular smooth muscle resulting in constriction of nasal blood vessels

Question 12

Oral vs topical decongestants pharmacokinetcs

Answer 12

topical: prompt effect. Phenylephrine has short (4hr) duration. Oxymetazoline has longer duration (6-12hrs). Oral: Longer duration of action and unaffected y mucus, but less vasoconstriction than topical. Pseudoephedrine is safest, phenylephrine blood levels are hard to preduct due to differences in metabolism (hepatic).

Question 13

Topical decongestants side effects

Answer 13

rebound congestion due to ischemia/local irritation

Question 14

Oral decongestants side effects

Answer 14

Affects other vascular beds (not limited to nasal blood vessels) and can cause headaches, dizziness, nervousness, nausea, increased blood pressure / palpitations

Question 15

decongestant uses

Answer 15

allergic rhinitis and viral cold infections

Question 16

List antitussive agents

Answer 16

Codeine/hydrocodone (controlled substances), Dextromethorphan

Question 17

Antitussive agents MOA

Answer 17

Central and peripheral actions. Codeine and dextromethorphan are agonists at endogenous opioid receptors that act to depress the cough center in brain stem. Dextromethorphan is most common OTC

Question 18

Antitussive agents side effects

Answer 18

Codeine: nausea, drowsiness, constipation, allergic rxns. Dextromethorphan: drowsiness, GI upset, PCP like effects at 50-100X therapeutic.

Question 19

antitussive uses

Answer 19

some use in cough associated with viral cold, allergic rhinitis

Question 20

Guidelines for treatment of acute cough due to common cold

Answer 20

1st generation antihistamine/decongestan and naproxen to block inflammation that stimulates cough afferents. Antitussives show mixed results

Question 21

Guidelines for treatment of cough due to upper airway cough syndrome

Answer 21

1st generation antihistamine/decongestant (e.g., brompheniramine/pseudoephedrine)

Question 22

Name an expectorant and a mucolytic agent

Answer 22

expectorant: guaifenesin. Mucolytic: N-Acetylcysteine

Question 23

Expectorant MOA

Answer 23

proposed to stimulate respiratory tract secretions to decrease their viscosity and enhance mucociliary removal plus ejection of phlegm and sputum. Increased fluid intake or use of vaporizer may more effective

Question 24

Expectorant side effects

Answer 24

GI upset

Question 25

Mucolytics MOA

Answer 25

Splits disulfide linkages between mucoproteins resulting in decreased viscosity of pulmonary mucus secretions. Also possesses antioxidant properties

Question 26

mucolytics administration

Answer 26

inhalation

Question 27

mucolytics side effects

Answer 27

May trigger bronchospasm (concerning in COPD), nausea, vomiting, rhinorrhea

Question 28

Uses of expectorants and mucolytics

Answer 28

some use in viral cold infections and COPD