Respiratory Drugs

Question 1

Histamine receptors

Answer 1

H1 - mediates vasodilation and bronchoconstriction. Gq

• H2- Located in GI, Gs, lead to gastric acid secretion
• H3 is autoreceptors

Question 2

H1 1st generation

Diphenylhydramine, chlorpheniramine

Answer 2

• Histamine receptor blockers decrease nasal discharge and bronchoconstriction
• Also have significant alpha and muscarinic blocking properties leading to side effects (CCC) Convulsions, Cardio, Coma (Rare to be this extreme)
• Used for allergy, motion sickness, sleep aid.
• Can also treat parkinson symptoms associated with antipsychotics

Question 3

H1 Second Generation

-Loratadine, ceterizine, fexofenadine

Answer 3

• Inhibit H1 receptors, used for allergy,

- Don’t cross BBB and have no sedative S/E

Question 4

Albuterol

Answer 4

• Short acting beta 2 agonist used for treatment of acute attack
• Binds to beta 2 receptor Gs leading to increase cAMP and bronchodilatoin
• Tachyphylaxis and palpitations are S/E

Question 5

Salmeterol, Formeterol

Answer 5

• Long acting beta agonists
• Same action as albuterol but longer half life
• Increased risk of arrythmias and tremor
• Not used as monotherapy

Question 6

Theophyline

Answer 6

• Methylxanthine that antagonizs PY adenosine receptor
• Leads to decreased vasodilation and also has PDE activity to incerase intracellular cAMP levels
• Narrow theruputic index and causes neuro and cardiotoxicity, so rarely used
• Blocks adenosine actions (SVT)

Question 7

Ipratropium

Answer 7

• Inhaled muscainic competitive antagonist that decreases bronchoconstriction
• M3 receptors are responsible for bronchoconstriction Gq
• M2 is Gi on cardiac and M1 is Gq on glands
• Minimal systemic effects when inhaled
• Used to treat asthma and COPD

Question 8

Tiotropium

Answer 8

-Similiar action on M3 receptors, but longer half life

Question 9

Fluticasone, Beclomethasone

Answer 9

• Inhaled steroids used as first line treatment for asthma prevention
• Cause decrease cytokine production anad reduced inflammation (NFkb)
• May cause oral thrush

Question 10

Montelukaust, Zafiralukast

Answer 10

• Competetive antagonist at leukotriene receptors
• C5, D5, E5, mediate bronchoconstriction
• B5 mediates neutrophil chemotaxis
• Used especially for aspririn induced asthma

Question 11

Zilueton

Answer 11

-Inhibits 5 lipoxygenase pathway and reduces leukotriene production from arachadonic acid

Question 12

Cromylyn

Answer 12

• Stabalizes mast cells and prevents histamine release

- Histamine causes bronchoconstriction and vasodiltion seen in acute phase of asthma attack

Question 13

Omalizumab

Answer 13

• monoclonal antibody to serum IgE
• Lowers effective IgE concentraion that will reduce likilhood of crosslink on mast cells
• Used in asthma that is resistant to steroids and beta agonists

Question 14

Guaifinesin

Answer 14

-Expectorant that thins respiratory secretions

Question 15

N-Acetlycysteine

Answer 15

• Forms disulfie bonds and disrupts mucus plugs in CF patients
• Also used to regnerate reduced glutathione in acetomenaphin poisoning

Question 16

Bonsentan

Answer 16

• Endothelin 1 antagonist

- Prevents vasoconstriction in pulmonary hypertension

Question 17

Dextromethorphan

Answer 17

• Coedeine analog that works as an antitussive
• Antagonizes NMDA receptor decreasing cough reflux
• Mild opiod effects, if overdose treat with naloxone

Question 18

Pseudophedrine, phenylephrine

Answer 18

• alpha agonist (sympathomimetic) in the nasal mucosa cause constriction and decresed rhinorrhea and can open eustachian tubes
• Have stimulant effects and may cause CNS stimulation and anxiety
• Also hypertension

Question 19

Methacholine

Answer 19

-AchR agonist and used to provoke asthma to clinically diagnose