ON CALL PLUS GLUCOMETER is a blood glucose monitoring system used to check the blood sugar level of an individual. Normal glucose levels before eating should be 5.9 millimoles per litre and below. The blood sugar readings taken before food are referred to as fasting blood glucose. The normal blood sugar readings after eating should be 7.8 millimoles per litre and below. It is advisable to pay your doctor a visit if you notice any higher-than-normal figures.