Lactose intolerance test


Lactose tolerance test

A normal response to 50 grams of lactose is a rise in the plasma glucose of greater than 1.2 mmol/L.

The most common cause of lactose intolerance is "acquired lactose intolerance of the adult", which is actually a native physiological condition in which the brush border disaccharidase lactase is lost in the adult.

European populations have a relatively low incidence of the above and hence reduction of gastro-intestinal lactase activity in the adult is considered to be a path

Patient Instructions:

Fast from midnight the previous evening.

Appointment Notes:

We now recommend our breath hydrogen and methane tests for lactose intolerance instead of these blood tests (May 2017)

Test takes 2.5 hours and patient should fast from midnight the previous evening.

Sample Requirements:

Collect a fasting blood sample into a fluoride oxalate blood tube. Give the patient 50 grams of lactose dissolved in water and collect further fluoride oxalate samples at 30 mins, 1hr, 1.5hrs, 2hrs & 2.5 hrs. Label each sample with the time it was taken & patient name.

Postal Samples Acceptable:


For further details please contact the laboratory at: