Effect of Plumbago zeylanica Linn Root Extract on Haematological Parameters in Laboratory Animals

Abstract

Plumbago zeylanica Linn enjoys considerable folkloric used in the management of many medical conditions and literature sources contain reports of its many pharmacological effects. Despite this widespread use, its haematological effects and toxicity remain largely unknown. This study investigates the haematological effects of Plumbago zeylanica Linn root extract in laboratory animals. Oral acute toxicity (LD50) was assessed by Lorke’s method and haematological effects by the 14 day repeated oral dose procedure. Sixteen albino Wistar rats divided into four groups were used for the haematological investigations. Group one was the control and received distilled water only by the oral route. Groups two to four received 500, 1000 and 1500 mg/kg body weight respectively of the root extract daily. After 14 days animals were sacrificed and blood collected for haematogical investigations. We found oral acute toxicity of the root extract to be more than 5000 mg/kg body weight. There were no statistically significant differences in haematological parameters - red blood cells, haemoglobin, total white blood cell counts and differentials and; haematological indices (parked cell volume, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration) – in treated animals relative to the control group at the P < 0.05 level. The root extract of Plumbago zeylanica Linn displays no haematological toxicity as it showed no effect (adverse or otherwise) on haematological parameters in laboratory animals. This justifies the extensive folkloric use to which the plant has been deployed.