This study was designed to compare the effect of fresh stem juice and aqueous stem juice extract of Costus afer on the stomach of paracetamol treated rats. Ld50 of the fresh stem juice and aqueous stem juice extract was determined by the modified Lorke’s method using twenty one (21) male mice and was determined to be 223.61 mg/kg and 353.55 mg/kg respectively. Twenty eight (28) adult male Wistar rats were used for the experiment. The animals were weighed before and after the experiment. They were randomly divided into seven groups of four animals in each group as follows. Group A: the control group was given feed and water ad libitum. Groups B - G served as the experimental groups. Group B was administered with 28.57 mg/kg of paracetamol. Group C was administered with 44.72 mg/kg of fresh stem juice extract of Costus afer. Group D was administered with 70.71 mg/kg of aqueous stem juice extract of Costus afer. Group E was administered with 28.57 mg/kg of paracetamol and 44.72 mg/kg of fresh stem juice of Costus afer .Group F was administered with 28.57 mg/kg of paracetamol and 70.71 mg/kg of aqueous stem juice extract of Costus afer. Group G was administered with 28.57 mg/kg of paracetamol and 100 mg/kg of silymarin. All administrations were carried out within 21 days. Administration was done orally using an orogastric tube. After the 21 days the animals were sacrificed by chloroform inhalation anesthesia and their stomach harvested, fixed in 10 % buffered formalin, processed and stained with hematoxylin and eosin staining technique. They were observed under a light microscope and the following observations were made. Group A showed normal histoarchitecture of the gastric epithelium. Group B showed severe atrophy of the gastric epithelium tissues. Degenerations in the stomach tissues where also mildly observed in groups C, D, E, F and G as compared to the paracetamol treated group. In conclusion, from this research it has been observed that oral administration of C. afer is toxic at the dosage above 223.61 mg/kg at fresh juice and 353.51 mg/kg at aqueous extract for of 21days, and it offered little protective effect on the stomach treated with paracetamol.
Keywords: Costus afer, Stomach, Paracetamol.