Bronchodilators
| Class | Drugs | Mechanism | Onset/Duration | Use | Key Points |
|---|---|---|---|---|---|
| SABA (Short-acting beta-2 agonist) | Albuterol (Ventolin, ProAir), levalbuterol (Xopenex) | β2 agonist → smooth muscle relaxation → bronchodilation; also stimulates mucociliary clearance | Onset: 5–15 min; Duration: 4–6 hr | Asthma rescue, COPD exacerbation, bronchospasm, hyperkalemia (albuterol drives K+ into cells) | Side effects: tachycardia, tremor, hypokalemia (high doses). Levalbuterol = R-isomer of albuterol; fewer cardiovascular side effects but more expensive |
| LABA (Long-acting beta-2 agonist) | Salmeterol (Serevent), formoterol (Foradil), indacaterol (Arcapta), olodaterol | β2 agonist; prolonged binding to β2 receptor | Duration 12–24 hr | COPD maintenance (monotherapy or with LAMA); asthma maintenance (ALWAYS with ICS — never monotherapy) | LABA MONOTHERAPY in asthma is CONTRAINDICATED (Black box warning — increased asthma deaths); always combine with ICS. Formoterol: fast-onset LABA (can use as rescue in SMART regimen) |
| SAMA (Short-acting muscarinic antagonist) | Ipratropium (Atrovent) | M1/M3 muscarinic antagonist → reduces bronchoconstriction, reduces secretions | Duration 4–6 hr | COPD (add-on to SABA for exacerbations); asthma exacerbations (add to albuterol in ED) | Side effects: dry mouth, urinary retention, constipation, tachycardia; avoid in narrow-angle glaucoma (may worsen); NOT absorbed systemically — minimal side effects inhaled |
| LAMA (Long-acting muscarinic antagonist) | Tiotropium (Spiriva), umeclidinium (Incruse), aclidinium (Tudorza), glycopyrrolate | M1/M3 muscarinic antagonist; prolonged duration (once daily) | Duration 24 hr (tiotropium) | COPD (1st-line maintenance); asthma (add-on for uncontrolled asthma on ICS+LABA) | Tiotropium: most evidence in COPD; reduces exacerbations (UPLIFT trial). Same anticholinergic side effects as SAMA. Use with caution in BPH, narrow-angle glaucoma |
| Methylxanthines | Theophylline, aminophylline (IV) | Phosphodiesterase inhibitor → ↑cAMP → bronchodilation; also stimulates respiratory drive; anti-inflammatory | Oral; IV available | Severe COPD (3rd-line add-on); historically used for asthma; IV aminophylline for severe asthma/COPD exacerbation | NARROW THERAPEUTIC INDEX (10–20 mcg/mL); toxicity: seizures, arrhythmias, N/V. Many drug interactions (CYP1A2 — cigarette smoking, ciprofloxacin, macrolides change levels) |
Inhaled Corticosteroids (ICS)
| Drug | Low Dose | Medium Dose | High Dose |
|---|---|---|---|
| Fluticasone propionate (Flovent) | 88–264 mcg/day | 264–440 mcg/day | >440 mcg/day |
| Budesonide (Pulmicort) | 180–540 mcg/day | 540–1080 mcg/day | >1080 mcg/day |
| Beclomethasone (Qvar) | 80–240 mcg/day | 240–480 mcg/day | >480 mcg/day |
🏥 ICS Prescribing PearlsMechanism: reduce airway inflammation (IL-4, IL-5, IL-13 signaling), reduce eosinophils, reduce mucus hypersecretion. Side effects: oral candidiasis (instruct patient to rinse mouth with water after each use), dysphonia (hoarseness), potential HPA axis suppression with high doses. Systemic absorption minimal at low-medium doses. ICS are cornerstone of asthma control (Step 2 and above). In COPD: ICS-containing regimens for patients with high eosinophils (>300 cells/mcL) or frequent exacerbations.
Combination Inhaler Regimens
| Combination | Examples | Use |
|---|---|---|
| ICS + LABA | Fluticasone/salmeterol (Advair), budesonide/formoterol (Symbicort), fluticasone/vilanterol (Breo Ellipta), mometasone/formoterol (Dulera) | Asthma Step 3–4 (preferred controller); COPD with high eosinophils/exacerbations |
| LAMA + LABA | Umeclidinium/vilanterol (Anoro Ellipta), tiotropium/olodaterol (Stiolto), glycopyrrolate/formoterol (Bevespi) | COPD maintenance (preferred dual bronchodilator therapy for moderate-severe COPD) |
| ICS + LABA + LAMA (Triple therapy) | Fluticasone/vilanterol/umeclidinium (Trelegy Ellipta), budesonide/formoterol/glycopyrrolate (Breztri) | COPD with high exacerbation risk, or uncontrolled on dual therapy |
🎯 Boards Pearl — SMART RegimenSMART (Single Maintenance And Reliever Therapy): budesonide/formoterol (Symbicort) used as BOTH daily controller AND rescue inhaler (replacing SABA). Formoterol has fast enough onset for rescue use. GINA guidelines support SMART for mild-moderate asthma — reduces severe exacerbations. Reduces overuse of SABA (high SABA use = marker of poor control).
Biologics for Severe Asthma
| Drug (Brand) | Target | Indication | Notes |
|---|---|---|---|
| Omalizumab (Xolair) | Anti-IgE | Moderate-severe allergic asthma; elevated IgE; sensitized to year-round allergen | SQ q2–4 weeks; reduces exacerbations 25–50%; monitor for anaphylaxis post-injection (30 min); also approved for CIU (chronic idiopathic urticaria) |
| Mepolizumab (Nucala) | Anti-IL-5 | Severe eosinophilic asthma (eosinophils ≥150 cells/mcL) | SQ monthly; reduces exacerbations ~53%; also approved for EGPA, COPD with eosinophilia |
| Benralizumab (Fasenra) | Anti-IL-5Rα | Severe eosinophilic asthma | SQ q4 weeks × 3 doses then q8 weeks; directly depletes eosinophils; rapid eosinophil reduction |
| Dupilumab (Dupixent) | Anti-IL-4Rα (blocks IL-4 + IL-13) | Moderate-severe asthma with eosinophilic phenotype OR oral corticosteroid-dependent; also atopic dermatitis, CRSwNP, EoE, COPD | SQ q2 weeks; improves lung function, reduces exacerbations; injection site reactions; conjunctivitis; no anaphylaxis risk like omalizumab |
| Tezepelumab (Tezspire) | Anti-TSLP (thymic stromal lymphopoietin) | Severe uncontrolled asthma regardless of eosinophil count — broadest indication | SQ monthly; reduces exacerbations across all asthma phenotypes (eosinophilic AND non-eosinophilic) |
Systemic Corticosteroids
| Indication | Drug / Dose | Notes |
|---|---|---|
| Asthma exacerbation | Prednisone 40–60mg PO × 5–7 days (no taper for short courses); methylprednisolone IV for severe | Reduces need for hospitalization, speeds recovery; no added benefit of longer courses in most cases |
| COPD exacerbation | Prednisone 40mg PO × 5 days (REDUCE trial: equivalent to 14 days) | Reduces treatment failure and hospital LOS; no survival benefit; 5-day course standard of care |
| Croup (laryngotracheobronchitis) | Dexamethasone 0.15–0.6mg/kg PO/IM × 1 dose; nebulized epinephrine for severe | Single dose dexamethasone = standard of care; reduces return visits and hospitalization |
Pulmonary Antibiotics
| Indication | First-Line Treatment | Alternative | Duration |
|---|---|---|---|
| CAP (outpatient, no comorbidities) | Amoxicillin 1g TID or doxycycline 100mg BID | Azithromycin (avoid in high macrolide resistance areas) | 5 days |
| CAP (outpatient, with comorbidities or recent antibiotic use) | Amoxicillin-clavulanate + macrolide OR respiratory fluoroquinolone (levofloxacin 750mg daily or moxifloxacin 400mg daily) | Respiratory FQ monotherapy | 5–7 days |
| CAP (inpatient, non-ICU) | Beta-lactam (ceftriaxone, ampicillin-sulbactam) + macrolide (azithromycin) | Respiratory fluoroquinolone monotherapy | 5–7 days |
| CAP (ICU) | Beta-lactam + azithromycin OR beta-lactam + respiratory FQ; add MRSA coverage (vancomycin/linezolid) if risk factors | Penicillin allergy: aztreonam + respiratory FQ | 7–14 days (based on clinical response) |
| COPD exacerbation with purulent sputum | Azithromycin, doxycycline, or amoxicillin-clavulanate (based on local resistance patterns and prior exacerbation history) | Respiratory FQ if gram-negative risk (frequent exacerbations, prior FQ use) | 5–7 days |
| PCP pneumonia (HIV/immunocompromised) | TMP-SMX (Bactrim) DS BID × 21 days; add prednisone if PaO2 <70 or A-a gradient >35 | Atovaquone, clindamycin + primaquine, or pentamidine | 21 days |
🎯 Boards PearlRespiratory fluoroquinolones (levofloxacin, moxifloxacin): excellent S. pneumoniae + atypical organism coverage. AVOID as first-line to preserve for resistant cases. Azithromycin: prolongs QT — check for drug interactions (other QT-prolonging drugs). Atypical pneumonia ("walking pneumonia"): Mycoplasma, Chlamydophila → treat with macrolide or doxycycline (NOT beta-lactams — no cell wall). Legionella: respiratory FQ or macrolide; NOT beta-lactams.
VTE / PE Pharmacotherapy
| Scenario | Drug of Choice | Notes |
|---|---|---|
| Acute PE, hemodynamically stable | Rivaroxaban (15mg BID × 21d → 20mg daily) or apixaban (10mg BID × 7d → 5mg BID) — DOACs preferred | DOACs non-inferior to warfarin with less bleeding; no bridging needed; faster onset |
| Acute PE, massive (hemodynamically unstable) | Systemic thrombolytics: tPA (alteplase 100mg IV over 2 hrs); followed by anticoagulation | Absolute contraindications: active intracranial process, recent stroke within 3 months, major surgery within 10 days, recent serious bleed |
| PE in pregnancy | LMWH (enoxaparin) throughout pregnancy and 6 weeks postpartum (DOACs and warfarin contraindicated in pregnancy) | No anti-Xa monitoring needed unless extremes of weight or renal impairment |
| VTE secondary prophylaxis (provoked) | 3 months of anticoagulation; then stop and reassess | Provoked (surgery, immobility, hospitalization): 3 months then discontinue. Unprovoked: extended therapy indefinitely if low bleed risk |