In rural settings of Abakaliki, D. rotundifolia direct leaf extract is commonly used for diagnosis of suspected Plague-like diseases as well as management of redness associated with eyes injuries. However, there is limited information on bioactive compositions of this ethnomedicine. This study evaluated the homeopathic theragnostic effects, nutritional and bioactive compositions of the D. rotundifolia ethnomedicine. The diagnostic and anti-inflammatory effects were evaluated by interviewing herbalists and observing along with them, the biological effects on patients after being administered with the ethnomedicine. Blood samples of the patients were tested for Y. pestis F1 antigens. The bioactive composition of the extract was determined by GCMS and nutritional composition by proximate analysis. Administration of D. rotundifolia direct leaf extract on patients suspected of plague-like disease through the eyes, ears, nose or mouth, which showed exacerbated swelling and inflammation of the head regions within 30 minutes, was interpreted to indicate positive for plague-like diseases by herbalists. Laboratory investigation confirmed 97.1% (68/70) of patients diagnosed positive for plague-like disease using the ethnomedicine, were confirmed positive for Y. pestis F1-antigen. Application of the direct extract on eye injuries with redness, relieved pains and cleared the redness/inflammation within 2 days. GCMS analysis revealed the presence of seven (7) bioactive compounds including; pyrrolidine,2-butyl-1-methyl; Heptane,2,2-dimethyl; 2,4-dihydroxybenzaldehyde, 2TMS derivatives; Octane,3,5-dimethyl. 3,7,11,15-tetramethylhexadecane-1,2,3-triolsilylated, 1,8-nonadien-3-ol and 2,6-Dimethyldecane. Out of the seven compounds, two novel compounds were identified as 1,8-nonadien-3-ol and 2,6-Dimethyldecane. The study also showed that direct extract of D. rotundifolia contained high amounts of protein, carbohydrate and lipid bioactive compounds. The presence of these compounds is s