Abstract: Objective: To verify the PPVs of ten-medication antidote signals to facilitate in recognizing the probable ADRs and to evaluate their sensitivity to determine the same ADRs with the contemporary method of pharmacovigilance. Materials and Methods: The EMR database of King Abdulaziz University Hospital was make use of, from 01 October, 2014 to 30 April, 2015. Children of either sex between the ages 0-15 with recipients of one of the ten medication antidote signals were selected, recipient’ data was analyzed to confirm a harm by medical care, patients with no harm were excluded, such an episode is subsequently confirmed as an ADR by the Naranjo’s tool. Additionally, contributing factors of ADRs were also evaluated. Results: The incidence rate of ADRs detected from MASs was found to be 27.8%. In contrast, voluntarily reported ADRs were observed as meager 0.88% and from progress notes of the patients, it was merely 0.73%. Remarkably, the total number of MASs observed in this study was 864 and 241 were confirmed as ADRs, the propensity of this scrutiny was apparently in the proportion of approximately1:3. Furthermore, ADRs were significantly higher in 0-1 years of age group and higher propensity of ADRs to the extent of 78.4% were observed with intake of 5-6 drugs. Moreover, preventable ADRs were identified in the range of 0-76.1% while severity of ADRs was detected in the range of 0-42.1%. Conclusion: Detection of ADRs by voluntary spontaneous reporting is characterized by under-reporting with the ultimate result of jeopardizing the patient safety. The methodology of ADRs detection by medication antidote signal, in this study has revealed the unique opportunity of high detection rate of ADRs with minimum cost, efforts and high precision. Moreover, this method seems to be quite adaptable and practical in view of the widespread availability of computerized medical information.