Introduction
Qvar Redihaler (beclomethasone dipropionate HFA) is an inhaled corticosteroid (ICS) approved for the maintenance treatment of asthma as prophylactic therapy in patients 4 years and older. It delivers medication via a breath-actuated inhaler that doesn't require coordination between actuation and inhalation, making it potentially easier to use than traditional metered-dose inhalers.
Mechanism of Action
Beclomethasone dipropionate is a synthetic corticosteroid that exerts potent anti-inflammatory effects in the airways. The drug binds to glucocorticoid receptors in lung tissue, leading to:
- Inhibition of inflammatory cell migration and activation
- Downregulation of cytokine production
- Decreased mucus secretion
- Reduction in airway hyperresponsiveness
- Stabilization of mast cells and other inflammatory mediators
The Redihaler technology delivers an extrafine aerosol with a mass median aerodynamic diameter of approximately 1.1 μm, allowing for enhanced deposition in both large and small airways.
Indications
- Maintenance treatment of asthma as prophylactic therapy in patients 4 years and older
- Not indicated for relief of acute bronchospasm
Dosage and Administration
Adults and adolescents (12 years and older):- Mild to moderate asthma: 80-320 mcg twice daily
- Severe asthma: Up to 640 mcg twice daily
- Starting dose: 40 mcg twice daily
- Maximum dose: 160 mcg twice daily
- Shake well before each use
- Prime with 4 test sprays before first use or if not used for more than 10 days
- Breathe in deeply and forcefully through mouthpiece
- Rinse mouth after each use to prevent oral candidiasis
- No need to coordinate pressing and breathing
- Hepatic impairment: Use with caution
- Renal impairment: No dosage adjustment necessary
- Elderly: No specific dosage recommendations
Pharmacokinetics
Absorption: Systemic absorption occurs primarily through the lung tissue with minimal gastrointestinal absorption due to extensive first-pass metabolism. Distribution: Binds extensively to plasma proteins (87%). Volume of distribution is approximately 20 L/kg. Metabolism: Undergoes extensive first-pass metabolism via hydrolysis to beclomethasone 17-monopropionate (active metabolite) and beclomethasone (inactive metabolite) primarily by CYP3A4. Elimination: Primarily eliminated in feces (60%) with lesser amounts in urine (12%). Terminal half-life is approximately 2.8 hours.Contraindications
- Hypersensitivity to beclomethasone dipropionate or any component of the formulation
- Primary treatment of status asthmaticus or other acute episodes of asthma requiring intensive measures
- Active or quiescent tuberculosis infection of the respiratory tract
- Untreated fungal, bacterial, or viral infections
Warnings and Precautions
Systemic Effects: Long-term use of high doses may result in HPA axis suppression, growth retardation in children, decreased bone mineral density, cataracts, and glaucoma. Local Effects: May cause oropharyngeal candidiasis and dysphonia. Rinsing mouth after use reduces risk. Paradoxical Bronchospasm: May occur with immediate increase in wheezing after dosing. Discontinue immediately if this occurs. Immunosuppression: Patients taking corticosteroids may be more susceptible to infections. Osteoporosis: Long-term administration should be accompanied by adequate calcium and vitamin D intake. Ophthalmic Effects: Regular ophthalmologic examinations recommended with long-term use.Drug Interactions
Strong CYP3A4 Inhibitors: (e.g., ketoconazole, ritonavir) - May increase systemic corticosteroid effects and adverse reactions. Use with caution. Other Corticosteroids: Additive systemic effects when used with other corticosteroid-containing medications. Live Vaccines: Avoid administration of live vaccines in patients receiving immunosuppressive doses of corticosteroids.Adverse Effects
Common (>1%):- Headache (12%)
- Pharyngitis (8%)
- Nasopharyngitis (7%)
- Upper respiratory tract infection (6%)
- Oral candidiasis (3%)
- Adrenal suppression
- Growth retardation in children
- Osteoporosis
- Glaucoma and cataracts
- Anaphylaxis (rare)
- Paradoxical bronchospasm
Monitoring Parameters
- Asthma symptoms and peak flow measurements
- Height and growth velocity in pediatric patients
- Signs/symptoms of oral candidiasis
- Ophthalmologic examinations with long-term use
- Bone mineral density in patients at risk for osteoporosis
- Adrenal function in patients switching from systemic corticosteroids
- Clinical signs of infection
Patient Education
- Use regularly as prescribed, not for acute relief
- Rinse mouth with water after each use without swallowing
- Clean inhaler weekly with dry cloth
- Keep track of dose counter
- Do not exceed prescribed dosage
- Report any signs of infection, vision changes, or decreased growth (in children)
- Carry a short-acting bronchodilator for acute symptoms
- Do not stop abruptly if using long-term without medical supervision
- Inform all healthcare providers about asthma medication use
- Schedule regular follow-up appointments with healthcare provider
References
1. FDA Prescribing Information: Qvar Redihaler (beclomethasone dipropionate HFA) 2. Global Initiative for Asthma (GINA) Guidelines, 2023 3. National Asthma Education and Prevention Program. Expert Panel Report 3 (EPR-3) 4. Kelly HW. Comparison of inhaled corticosteroids. Ann Pharmacother. 2021;55(11):1419-1429 5. Patel M, Pilcher J, Pritchard A, et al. Efficacy and safety of maintenance and reliever combination budesonide-formoterol inhaler in patients with asthma at risk of severe exacerbations: a randomised controlled trial. Lancet Respir Med. 2022;10(5):471-486 6. Reddel HK, Bacharier LB, Bateman ED, et al. Global Initiative for Asthma Strategy 2021: executive summary and rationale for key changes. Eur Respir J. 2022;59(1):2102734 7. ClinicalTrials.gov: Studies on beclomethasone dipropionate HFA inhalation aerosol 8. manufacturer's product information and clinical trial data