The control of Periplaneta americana in urban areas is a key factor in human health, since cockroaches are transmitters of bacteria, protozoa, helminths, fungi and viruses. The present study analyses the effectiveness of different insecticides on controlling cockroach populations. Aseries of treatments applied to the sewer system in the city of Cordoba (Spain) was evaluated. The treatments included the use of different compositions such as chlorpyrifos, diazinon, pyriproxyfen and triflumuron. Based on the results, itwas observed that chemical products such as chlorpyrifos (Empire 20®) or diazinon (Diacap®) produced better results in the control of P. americana than IGRs such as pyriproxyfen (Sumilarv 10 EC®) or triflumuron (Starycide®). The two most efficient products (chlorpyrifos and diazinon) were tested again and chlorpyrifos was shown once more to generate better results. Finally, two different formulae of these products were analysed for efficiency (Empire 20® and M.K.I. 20 LE®) and no statistical difference were observed between them.According to the results, the most efficient product for controlling P. americana in the city of Cordoba is chlorpyrifos, regardless of the formula employed, followed by diazinon and finally by the IGRs, which did not produce such good results.