The majority of plants used in traditional medicine can have toxic effects. Two hundred grams of vegetable powder of each species were macerated, then filtered under vacuum on a Büchner. Tests for the detection of large groups of phytochemicals were carried out. Microbiological quality control has aimed mainly at Salmonella, yeasts and molds, total coliforms and fecal coliforms. The study of acute toxicity was conducted according to guideline 423 of the OECD protocol and subacute toxicity was studied from guideline 407 of the OECD. The blood samples were taken from the fasted rats and under anesthesia with diethyl ether. The hematological parameters were measured by the Medonic (Beckman coulteur-USA-). The masses obtained after drying the macerate in an oven at 50 °C were 28 g and 9.3 g respectively for Picralima nitida and Musanga cecropioides with respective yields of 14% and 4.65%. The tests for microbial germs likely to reveal the contamination of the extracts were negative. There were no anomalies in the parameters studied during acute toxicity, except for the aggressiveness of rats during the first day. No deaths have been recorded. The LD50 is therefore greater than 5000 mg/Kg. After twenty-eight days of observation during the study of subacute toxicity, variations in numerous parameters studied were observed in different batches. The average body weights of rats in all batches increased during the observation period. Analysis of the biochemical parameters of the rats' blood showed that many parameters were higher in the control group than in the treated groups.