Respiratory System Drugs Flashcards
Mechanism:
Sildenafil
Tadalafil
(-afil)
Pulmonary HTN drug (also treats ED):
Inhibits PDE-5 → increasing cGMP → prolonging vasodilatory effect of nitric oxide (NO)
Mechanism: Theophylline
Inhibits phosphodiesterase (PDE) → increasing cAMP (due to decrease cAMP hydrolysis) → bronchodilation
Adverse effects: Theophylline
- Cardiotoxicity
- Neurotoxicity
Usage limited due to narrow therapeutic index
Metabolized by cytochrome P-450 (substrate)
Mechanism: Albuterol
Short-acting beta-2 agonist:
Relaxes bronchial smooth muscle
Used during acute exacerbation
Mechanism: Montelukast
Antileukotriene:
Block leukotriene receptors (CysLT1)
Especially good for:
- Aspirin-induced
- Exercise-induced asthma
Class: Promethazine
1st generation antihistmaine
Clinical use:
Tiotropium
Ipratropium
(-tropium)
Asthma
COPD
Class: Hydroxyzine
1st generation antihistmaine
Adverse effects:
Pseudoephedrine
Phenylephrine
- Hypertension
- Rebound congestion if used more than 4-6 days
- Pseudoephedrine: CNS stimulation/anxiety
Clinical use:
Beclomethasone
Fluticasone
Budesonide
1st-line therapy for chronic asthma
Mechanism:
Tiotropium
Ipratropium
(-tropium)
Muscarinic antagonists:
Competitively block muscarinic receptors, preventing bronchoconstriction
Tiotropium = long-acting
Class: Cetirizine
2nd generation antihistamine
Class/mechanism: Pseudoephedrine
Alpha-adrenergic agonists
Used as nasal decongestants
Clinical use: 1st generation antihistamines
Allergy
Motion sickness
Sleep aid
Mechanism of antihistamines
Reversible inhibitors of H1 histamine receptors
Mechanism: Omalizumab
Anti-IgE monoclonal therapy:
Binds mostly unbound serum IgE and blocks binding to FceRI
Mechanism: Formoterol
Long-acting beta-2 agonist used for asthma prophylaxis
Adverse effects:
Bosentan
Ambrisentan
(-sentan)
Hepatotoxic (monitor LFTs)
Class/mechanism: Phenylephrine
Alpha-adrenergic agonists
Used as nasal decongestants