The aim of this study was to evaluate the immunopotentiating effect of IAD in broiler chickens either vaccinated or unvaccinated and to evaluate the safety profile of IAD after treatment with escalating doses. To assess the immunological effect of IAD, eighty chicks were used and divided into four groups. First group kept as control group, second received Isoprinosine (16.3 mg/kg, day after day), third received a routine New Castle disease virus vaccine and the last group received both treatments of Isoprinosine and ND vaccine. The second part of the study aimed to evaluate the safety profile of IAD, to achieve this aim eighty chicks were used, divided equally and given different concentration of IAD 8.15, 16.3, 32.6 mg/kg day after day repetitively. We concluded that, IAD enhanced both nonspecific and specific immune responses in broiler chicken, especially in vaccinated ones, in terms of increased antibody and decreased NDV titers, indicated by HI and PCR, respectively. Also, IAD showed dose-dependent good safety profile, including blood picture, organ function profile and metabolic parameters, indicated by biochemical analyses.