This was a 3 months prospective, open label, and parallel study to test the efficacy of 3 different corticosteroids in the management of interstitial lung diseases. Followed by a pharmacoeconomic analysis to find which regimen (betamethasone, dexamethasone or prednisolone) is the most cost-effective.

Three different corticosteroid regimens were evaluated for the management of interstitial lung diseases (ILDs) with specific focus on hypersensitivity pneumonitis (HP) where the patients were divided into 3 treatment groups:

• Group I: patients receiving weekly pulse doses of betamethasone IM injection (equivalent dose to that of prednisolone daily dose in a week).

• Group II: patients receiving weekly pulse doses of dexamethasone IV injection (equivalent dose to that of prednisolone daily dose in a week).

• Group III: patients receiving oral prednisolone daily (dose range 15-20 mg/day).

  10 mg oral prednisolone oral ≡ 1.5 mg dexamethasone intravenous ≡ 1.2 mg betamethasone intramuscular.

After the administration of the above-mentioned medications, the patients were followed-up over 3 months to evaluate their disease progression. Informed consent was obtained from all subjects or their surrogate after explanation and understanding of the nature, purpose, and potential risks of the study. The study protocol was approved by the Ethics Committee, Faculty of Pharmacy, Cairo University (protocol serial number: CL (2183)) .

A special patient information sheet was designed to collect all information required for data analysis. The sheet was designed to be divided into several sections:

1. Demographic Data The first section of the patients' information sheet was designed to accommodate the basic general and demographic data (name, address, age, telephone number, social status, weight, and height of the patient). These details were documented from the patient's medical notes.
2. Medical Data Medical records were used to obtain other data including date and time of examination, the diagnosis, medications on recruitment (if any), smoking habits, patient's medical history, in addition to the patient's medication history.
3. Parameters Used to Measure Effectiveness as KL-6, PFTs, ESR, CRP
4. Parameters to Evaluate Treatment Safety Liver Function Tests, Random Blood Glucose (RBG), Blood Pressure

Cost Effectiveness Analysis The study is designed from patient perspective where the direct medical costs as well as the indirect costs (e.g., loss of patients' income) are studied. The costs are collected directly from the patient prospectively throughout the study period. All costs were actual covering the treatment expenses as: the cost of the medications, the cost of administration, the cost of the hospital stay due to ILD during the study period, the cost of the physician's visit and the cost afforded by the patient in order to administer the recommended medication, any extra costs due to exacerbations or adverse effects due to the use of corticosteroids and costs of transportation and days-off.

Inclusion Criteria:

• Patients with ILD (hypersensitivity pneumonitis) with age between18 and 65 years old.
• Symptoms including dry cough and shortness of breath.
• Significant decrease in pulmonary function (desaturation by 4% after 6-minute walk distance), where the patients were no more controlled on their prednisolone maintenance therapy (up to 10 mg/day).
• Chest CT showing ground glass opacity and band of shadow.

Exclusion Criteria:

• Patients with any other organ affliction (heart failure (ejection fraction 40-50%), renal failure (decrease in glomerular filtration rate > 75%), or liver cirrhosis (transient elastography liver stiffness measurements 12.5-75.5 kPa)).
• Active infection.
• Patients on other immunosuppressive medications (e.g., cyclophosphamide) and anti-fibrotic (e.g., interferon, pirfenidone, endothelin-1 antagonist and tumor necrosis factor α modulator).
• History of pulmonary embolism (corticosteroids' use increase the risk of recurrence of pulmonary embolism).
• Pregnancy.