Asthma Drugs

Beta-2 agonists
    
    Metaproterenol, terbutaline, albuterol, salbutamol, isoetharine, salmeterol
    MOA: bronchodilation, also inc mucus clearance, dec microvasc perm, dec inflam cell mediator release
    Metered dose inhaler preferred over nebulizer due to lower side effects
    Short acting (albuterol) for acute Rx, long acting (salmeterol bid) for prophylaxis/maintenance
    PK: usually first pass effect
    Tox: tolerance due to receptor downregulation*, CV, CNS, hypoK, hyperGlc

Salmeterol
    
    Long acting beta-2 agonist for prophylaxis/maintenance
    PK: bid

Formoterol
    
    Long acting beta-2 agonist for prophylaxis/maintenance
    PK: bid

Ipratropium bromide
    
    MOA: Cholinergic & reflex bronchoconstr blocker
    Acute Rx (2nd line behind or in combination w/ beta-2 agonist)
    1st line COPD Rx
    PK: slightly slower onset than beta-2 agonists

Theophylline (methylxanthines)
    
    MOA: relaxes SMC -> bronchodilation
    Also inc resp mm contractility
    Acute Rx with caution
    PK: highly variable (indiv therapy, start at low dose), zero order elim at high dose, many drug interactions
    Tox: worse w/ higher serum conc*, CNS, (-) GI, (+) CV, (+) metabolic, diuresis

Systemic steroids
    
    Acute Rx with caution

Inhaled steroids
    
    Beclomethasone, triamcinolone, flunisolide, fluticasone, budesonide
    MOA: block phospholipase A2 -> dec inflam cell mediator release
    1st line prophylaxis/maintenance Rx, perhaps in combination with long acting beta agonist
    PK: use minimum dose req'd
    Tox: laryngeal myopathy*, Candida thrush*, ?cataracts, ?dec growth, osteoporosis

Advair(TM)
    
    Fluticasone + salmeterol
    Prophylaxis/maintenance Rx only
    PK: bid max

Cromolyn
    
    MOA: anti-inflammatory, details unclear
    Prophylaxis Rx against exercise & allergen challenge
    Rx allergic rhinitis
    Tox: HA, nausea

Nedocromil
    
    MOA: anti-inflammatory, broader than cromolyn
    Prophylaxis Rx against exercise & cold challenge

Zafirlukast
    
    MOA: leukotriene-R blocker
    Prophylaxis/maintenance Rx
    PK: oral bid, CYP-450 drug interactions
    Tox: HA, gastritis, parhyngitis, rhinitis, eosinophilic vasculitis (rare but serious)

Montelukast
    
    MOA: leukotriene-R blocker
    Prophylaxis/maintenance Rx
    Preferred over zafirlukast (no effect on CYP-450, no vasculitis)
    Steroid sparing therapy
    PK: qd

Zileuton
    
    MOA: 5-lipoxygenase inhibitor -> dec leukotriene synthesis
    Prophylaxis/maintenance Rx, but not used often
    PK: qid

Omalizumab
    
    MOA: human anti-IgE mAb
    Rx severe recurrent asthma, expensive
    PK: every 4 wks
    Tox: anaphylaxis