The high prevalence rate of diabetes mellitus (DM) in the developing world and its attendant high cost on healthcare have necessitated search for cheaper, effective and readily available alternative therapies in plants. One of such plants used in Nigeria is Newbouldia laevis (P. Beauv) (NLE). Its effect on erythrocyte fragility, membrane stability and haematological parameters in alloxan-induced diabetic rats for 21 days showed that Newbouldia laevis at 250 mg/kg reduced erythrocyte haemolysis to 11.08±2.50 % while Vitamin C (Ascorbic acid 200 mg/kg) reduced the haemolysis by 10.87±2.16 %. Glibenclamide (2 mg/kg) a standard oral antidiabetic drug reduced the haemolysis to 22.52±3.50 % all at the NaCl concentration of 0.85 %. It also demonstrated its ability to protect the liver, kidney and the pancreas especially at the dose rate of 250 mg/kg against alloxan-induced diabetic membrane destruction. It dose-dependently decreased the packed cell volume (PCV) from 43.67±7.34 % at the dose of 62.5 m g/kg to 33.64±6.34 % at the dose of 125.0 mg/kg and 28.33±3.67 % at the dose of 250 mg/kg. Haemoglobin concentration (Hb), reduced from 14.57±2.43 % at the dose of 62.5 mg/kg to 9.43±1.20 % at 250 mg/kg. But at the same time, it dose-dependently increased the white blood cell count (WBC) from 4.13±0.83 x 103 at the dose of 62.5 mg/kg to 6.26±1.3 x 103 at the dose of 250.0 mg/kg. In conclusion, Newbouldia laevis at 250 mg/kg has erythrocyte and membrane protection ability in alloxan-induced diabetic rats comparable to Vitamin C and glibenclamide, but has variable effects on haematological parameters that are within the normal ranges in diabetic rats.Keywords: Diabetes, Erythrocytes, Haematology, Membrane stability, Newbouldia laevi
