Generic Name

Flovent HFA

Mechanism

• Fluticasone propionate binds intracellular glucocorticoid receptors in airway smooth muscle and inflammatory cells.
• This complex translocates to the nucleus, initiating transcription of anti‑inflammatory genes (e.g., lipocortin‑1) and repressing pro‑inflammatory cytokines (IL‑4, IL‑5, IL‑13, TNF‑α).
• Result: ↓ eosinophilic inflammation, ↓ mucus production, ↑ airway smooth‑muscle tone, and ↓ bronchial hyperreactivity.

Pharmacokinetics

• Absorption: Rapid pulmonary deposition, ~30–50 % of the dose reaches systemic circulation via mucosal and alveolar pathways.
• Distribution: Extensive tissue binding; negligible systemic bioavailability after per‑dose; high protein binding (>90 %).
• Metabolism: Hepatic CYP3A4‑mediated 20β‑hydroxylation; metabolites are inactive.
• Elimination: Renal excretion (~90 % of parent and metabolites); half‑life ~7 h (pulmonary) and ~18 h (systemic).
• Drug interactions: Potentiated effects with potent CYP3A4 inhibitors (ketoconazole, clarithromycin).

Indications

• Moderate‑to‑severe persistent asthma in children ≥6 yrs and adults.
• Asthma exacerbations as maintenance therapy post‑reliever.
• Chronic obstructive pulmonary disease (COPD) exacerbation prevention (often combined with LABAs).

Contraindications

Warnings
• Respiratory infections: Monitor for post‑inhaler infections; caseate.
• Systemic adrenal suppression: Monitor in long‑term high‑dose therapy.
• Cushingoid features: Rare with standard doses; urgent review if signs appear.

Dosing

• Pulmonary administration: Shake, prime (if first‑use), mouth‑wash for 30 s, inhale slowly through the nose, hold breath 5–10 s.
• Co‑administration: If using LABAs or leukotriene modifiers, use a separate metered‑dose inhaler (MDI) or formoterol Salbutamol (Synergist®).

Adverse Effects

Common
• Oral candidiasis (thrush)
• Dysphonia (hoarseness)
• Local irritation (mouth, throat)

Serious
• Systemic hyper‑cortisolism (rare at therapeutic doses)
• Adrenal suppression (especially in poor inhaler technique, high cumulative doses)
• Ophthalmic complications (cataract, glaucoma) with chronic high exposure

Management
• Rinse mouth after use.
• Reduce dose or switch to non‑inhaled route if systemic signs appear.

Monitoring

• Pulmonary function: Spirometry (FEV₁, FVC) every 4–6 weeks or upon symptom change.
• Adrenal function: Morning cortisol if long‑term >6 mths or high dose.
• Ocular exam: Annual eye checkup in patients >12 yrs on >6 mths therapy.
• Inhaler technique: Re‑education at every encounter.

Clinical Pearls

• Prime before first use – ensures patient receives the full label dose, critical for children.
• Use a spacer – reduces deposition in the oropharynx, lowering thrush incidence.
• Adhere to wash‑out periods – when switching between fluticasone and beclomethasone, allow 4–6 weeks to avoid over‑exposure.
• CYP3A4 interaction – co‑administration with ketoconazole or macrolide antibiotics may increase systemic absorption by 20–40 %; consider dose adjustment.
• Low‑dose flare‑up – in mild asthma, 200 µg twice daily may suffice; step down to 100 µg once daily if stable for 3–6 months.
• Alternatives – if thrush persists despite rinsing, try natural mouth rinse (e.g., nystatin) or switch to mometasone furoate spacer formulation.

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• *References: UpToDate, FDA Label (Flovent HFA), American Thoracic Society, American College of Physicians.*