Gagal jantung adalah kondisi kronis pada sistem kardiovaskular yang memerlukan terapi kombinasi dengan jenis dan mekanisme berbeda sehingga dapat meningkatkan risiko potensi interaksi obat. Tujuan penelitian ini untuk mendapatkan persentase kasus pasien yang mengalami potensi interaksi obat serta mekanisme, tingkat keparahan, dan tingkat risiko potensi interaksi obat pada pasien gagal jantung di Instalasi Rawat Inap RSD Idaman Banjarbaru tahun 2023. Sumber data penelitian ini yaitu rekam medis pasien. Pengambilan data dilakukan secara retrospektif dan dianalisis secara deskriptif menggunakan Lexicomp Interact®. Hasil penelitian menunjukkan bahwa dari 126 kunjungan pasien, 96% (121 kunjungan pasien) mengalami potensi interaksi obat dengan 158 kombinasi obat serta 1.088 total kejadian potensi interaksi obat. Potensi interaksi obat berdasarkan mekanisme pada fase farmakokinetik sebesar 21,691% (236 kasus), fase farmakodinamik sebesar 78,309% (852 kasus). Potensi interaksi obat berdasarkan tingkat keparahan pada tingkat minor sebesar 11,213% (122 kasus), moderate sebesar 77,114% (839 kasus), dan major sebesar 11,673% (127 kasus). Potensi interaksi obat berdasarkan tingkat risiko pada tingkat risiko A sebesar 0,092% (1 kasus), tingkat risiko B sebesar 8,548% (93 kasus), tingkat risiko C sebesar 86,213% (938 kasus), tingkat risiko D sebesar 4,412% (48 kasus), dan tingkat risiko X sebesar 0,735% (8 kasus). 

Heart failure is a chronic condition of the cardiovascular system that requires combination therapy with different types and mechanisms, which can increase the risk of potential drug interactions. This study aims to determine the percentage of cases experiencing potential drug interactions, as well as the mechanisms, severity levels, and risk levels of potential drug interactions in heart failure patients at the Inpatient Installation of RSD Idaman Banjarbaru in 2023. The data source was patients’ medical records. Data were collected retrospectively and analyzed descriptively using the Lexicomp Interact®. The results showed that out of 126 patient visits, 96% (121 patient visits) experienced potential drug interactions with 158 drug combinations and a total of 1,088 potential interaction cases. Potential drug interactions based on mechanism were 21.691% (236 cases) pharmacokinetic phase and 78.309% (852 cases) pharmacodynamic phase. Based on severity level, potential drug interactions were minor 11.213% (122 cases), moderate 77.114% (839 cases), and major 11.673% (127 cases). Based on risk level, potential drug interactions were risk level A 0.092% (1 case), risk level B 8.548% (93 cases), risk level C 86.213% (939 cases), risk level D 4.412% (48 cases), and risk level X 0.735% (8 cases).