OBJECTIVES: To evaluate the utilization of sildenafil (ATC C02KX) in hospital in-patients. METHODS: A retrospective DUE analysis of 125 inpatient was conducted who were prescribed with Sildenafil between April 2014 – March 2015 from a West coastal region Hospital of southern Indian according to hospital records. The patients included were across all age groups. Defined daily dose (DDD)/100 bed days, the Prescribed daily dose (PDD) and the PDD to DDD ratio was studied along with its safety profile. RESULTS: Out of 125 patients, male predominance (54%) with a median age of 60 (IQR 47-68) was observed. Mean hospitalisation days were 9 (±4 SD). 80% of the patients prescribed were diagnosed with PAH (49% moderate, 31% severe), 6.4%: CHF, 2.4% with erectile dysfunction and 11.2% in those with insufficient documentation.  PAH as a result of Pulmonary origin (COPD, Asthma, Post TB, ILD) was seen in 81%, while with cardiac (Congenital, CHF, IHD) was 10% and with cor-pulmonale - 5%.  The DDD/100/bed days was 0.29 mg. PDD was 43.0 mg and the ratio of PDD/DDD ratio of Sildenafil was found to be 1.48.  Patient’s clinical outcomes were: improvement of functional status in 46%, persisting in 41%, 10% expired and 2% were discharged against medical advice. Hypotension was the significant ADR associated with Sildenafil in 28% and 1.6% with headache. CONCLUSIONS: Though close to half of the study patients showed symptomatic relief with sildenafil use in PAH patients, it was found to be ineffective in remaining 50% which suggests mixed therapeutic outcomes seen mainly in COPD patients which necessitates aggressive early disease management and rehabilitation programs.