Lactose Tolerance

By appointment only.
Community patients: contact CLS Patient Appointment Line at 403-777-5136 to book an appointment at any Patient Service Centre. Test cannot be collected by Mobile Collection Service (MCS).
Hospital patients: nursing unit to book appointment with on-site lab. 

Pediatric patients under 5 years of age:
Due to possible difficulty administering the drink, ordering physician must obtain approval by CLS Medical and Scientific Staff.  Contact Laboratory Information Center at 403-770-3600 for Pathologist-on-call information. An alternative non-invasive test is the Hydrogen Breath Test for Lactose Intolerance.


1 x 3 mL or 4.5 mL light green (mint) top PST tube for each timed specimen.  Gold top SST tube also acceptable.

0.2 mL heparinized plasma or serum

Minimum Whole Blood Volumes for Micro-Collections using Microtainers

Requires a fast of at least 8 hours.

Blood collections are performed at the following intervals: fasting, 30 minutes, 60 minutes, and 120 minutes.

Patient instruction sheet (form #CH3002) may be given to patient.

Order drink at least 2 days in advance.

• Sloane Square & Marlborough PSC, & RRL: order from CLS Purchasing.
• Other PSC sites: order from Sloane Square or Marlborough PSC.
• Extra-regional: order from DSC Accession at 403-770-3245

All PSC & extra-regional:
If patient weighs less than 23 kg (50 lb), order drink from DSC Accession at 403-770-3245 and state patient's weight.

The drink provided for Lactose Tolerance test includes the following ingredients:

• Lactose monohydrate
• Natural orange flavouring
• No artificial flavouring or colouring