The inflammation is a response to some injury aimed at reestablishing homeostasis of the affected tissue. The in vitro model using RAW 264.7 cells has been widely used, as experimental model to assess the inflammatory response. However, there is still no consensus on which inflammatory mediators should initially be measured to screen for possible anti-inflammatory effects. To determine the rationality of measuring different inflammatory mediators together with NO, we carried out this systematic review and meta-analysis. A total of 17 studies were included, and LPS-induced cells produced high NO levels compared to non-LPS induced, and this production was not related to cell density. TNF-α, IL-1β, and IL-6, also showed high levels after cells had been stimulated with LPS; however, these effects were related to cell density. Finally, was found that measurement of NO levels alone may be sufficient to screen for possible anti-inflammatory action in the context of this model.