Background: Inhaled corticosteroids (ICS) are the cornerstone of long-term asthma management because of their potent anti-inflammatory effects and ability to reduce exacerbations. Despite their favorable safety profile compared with systemic corticosteroids, prolonged or high-dose ICS therapy may result in systemic adverse effects, including hypothalamic-pituitary-adrenal (HPA) axis suppression. Budesonide and fluticasone propionate differ in pharmacokinetic and pharmacodynamic properties that may influence their potential for adrenal suppression; however, comparative evidence in Indian adults with asthma remains limited.

Objective: To compare the short-term effects of inhaled budesonide and fluticasone propionate on serum cortisol levels, pulmonary function, and asthma-related quality of life in adults with moderate persistent asthma.

Methods: This prospective randomized pilot study was conducted in the Department of Respiratory Medicine at a tertiary care hospital. The study enrolled 32 adults with moderate persistent asthma who were allocated in a 1:1 ratio to receive either inhaled budesonide (400 μg/day; n = 16) or fluticasone propionate (500 μg/day; n = 16) for 15 days. Morning fasting serum cortisol concentrations were measured at baseline and post-treatment as the primary outcome. Secondary outcomes included pulmonary function parameters (forced expiratory volume in one second [FEV₁], forced vital capacity [FVC], and peak expiratory flow rate [PEFR]) and Asthma Quality of Life Questionnaire (AQLQ) scores. Continuous variables were analyzed using paired and independent-samples t-tests, with effect sizes expressed as Cohen’s d. Statistical significance was established at p < 0.05.

Results: Both treatment groups demonstrated reductions in serum cortisol levels after 15 days of therapy. The mean reduction was numerically greater in the fluticasone propionate group compared to the budesonide group (−52.76 ± 81.2 nmol/L versus −34.54 ± 65.1 nmol/L; p < 0.001; Cohen’s d = 0.82). Improvements in AQLQ scores were observed in both groups (Budesonide & Fluticasone, +0.36 ± 0.02 and +0.34 ± 0.01, p = 0.001), while pulmonary function parameters remained comparable throughout the study period.

Conclusion: Short-term treatment with inhaled budesonide and fluticasone propionate improved asthma-related quality of life while producing measurable reductions in serum cortisol concentrations. Fluticasone propionate was associated with a greater decline in serum cortisol than budesonide under the investigated dosing regimen, indicating a potential for greater systemic corticosteroid exposure. The observed differences should be interpreted cautiously given the pilot nature, short duration, and dose differences between treatment groups. Larger, long-term studies incorporating dynamic endocrine testing are required to confirm these findings and guide optimal ICS selection.

KEYWORDS: Asthma, Inhaled Corticosteroids, Serum Cortisol, Adrenal Suppression, Quality of Life.