Abstract Tribolium castaneum is a critical stored-grain pest of nuts and cereals. Insecticides have traditionally been used to control it; however, their overuse can result in the development of insecticide resistance. Effective bait pesticides could be useful tools for slowing down the rate of insecticide-resistance development and improving the management of stored grain pests. Attractive toxic sugar bait (ATSB) systems are used with mosquitoes and flies; they lure pests with liquid foods that contain sugars but also an oral toxin. It is unknown whether the ATSB system is applicable to T. castaneum adults who prefer dry food products with reduced water content. The objective of this study is to develop an optimal ATSB system for T. castaneum control. Thus far, it found that T. castaneum consumed a gypsum block. The dietary intake of T. castaneum adult beetles was facilitated with added mannitol into gypsum block. Combining insecticides that are oral toxins of the pests with these facilitating sugars results in the death of the pest. Spirotetramat causes a significant reduction in fatty acid biosynthesis by inhibiting acetyl-CoA carboxylase. In this investigation, we have demonstrated that spirotetramat, at low concentrations, was lethal to T. castaneum adults, when used with the ATSB system, combined with mannitol. The lethality of chlorfenapyr, an inhibitor of mitochondrial ATP synthesis, to adult T. castaneum did not increase when used in the ATSB system with mannitol. These results show that the active ingredient used in the ATSB system is integral for beetle control. Increasing the oral delivery rate of insecticides using carbohydrates leads to increased lethality rates of stored-grain pests.