The current study examines the anti-dengue and antibacterial potential and in silico drug development of the andrographolide against the pathogens Staphylococcus aureus (1JIJ) and Pseudomonas aeruginosa (6MVN) and the dengue viral protein NS5. The phytochemical analysis identified the presence of flavonoids, alkaloids, saponins, tannins, phenols, glycosides, and steroids in the Andrographis paniculata methanolic leaf extract. Based on the GC-MS analysis, andrographolide was identified as the primary chemical constituent of the medicinal plant A. paniculata and the compound with the largest peak area among other compounds. The agar well diffusion method was employed to observe the antibacterial potential of the methanolic leaf extract against S. aureus and P. aeruginosa. The maximal inhibition zones were 15.6 ± 0.34 mm and 11.7 ± 0.42 mm, respectively. Additionally, andrographolide was docked with the NS5 viral protein and bacterial proteins, including S. aureus TyrRS (PDB: 1JIJ) and P. aeruginosa LasR PDB (ID: 6MVN), resulting in a docking score of - 20.7384 kJ/mol, - 15.0969 kJ/mol, and - 11.1171 kJ/mol, respectively. In summary, our molecular docking experiments with the identified andrographolide compound demonstrated its potential as a drug with anti-dengue viral and antibacterial properties.