Azadirachta indica is a plant known as an insecticide and an ixodicide. There are reports about the effectiveness of extracts prepared from its seeds and flowers in the laboratory; but the effectiveness of "rustic" extracts prepared from its leaves remains unknown. Therefore, the aim of this study was to determine the efficacy of aqueous and ethanolic extracts on adult female ticks Ripicephalus (Boophilus) microplus, used at different time periods after its preparation, knowing that the natural extracts do not have any preservatives nor stabilizing substances, and can lose composition as well as biochemical activity through time. The ticks used in this study were obtained from naturally infected cattle. They were divided into different groups which were exposed to pure extracts, and diluted extracts. They were also included in positive and negative control groups. We did the assays in triplicate using the immersion technique on adult ticks. The assays were carried out with 14-hour preparation, 30-day preparation, 60-day preparation, and 90-day preparation extracts, in order to determine their efficacy. We found ixodicide effect at the two fresh-pure extracts (14-hour preparation) though; it was lower than 60%. The ixodicide effect was notably reduced at the 30-day preparation extract, and it was absent at the 60-day preparation, and 90-day preparation extracts. The conclusion is that there was ixiodicide effect; but the extraction method did not allow the obtaining of the active principle, and that the extract decomposes through time.