Midwest · Lactose Tolerance Test
Lactose Tolerance Test in Illinois
Below is a plain-language overview of the lactose tolerance test. A lactose tolerance test helps assess how the body handles lactose, a sugar found in milk and dairy foods. It is used to look into symptoms that may be related to lactose sensitivity.
Lab requirements in Illinois
Here is what you need before ordering and completing the Lactose Tolerance Test in IL. Review each item and confirm the details with the collection lab.
- Physician's order
- Included. A physician's order is required for lab testing and is provided for you by our partner's physicians — no referral from your own doctor is needed.
- Fasting
- Fasting is required for this test — follow the collection lab's instructions.
- Preparation
- The collection lab will provide specific instructions, which often include fasting for a certain number of hours before the test. Follow those instructions exactly, and ask the lab about…
- Sample & visit
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Identification
- Bring the lab requisition form from your account. The collection lab may also ask for a government-issued photo ID.
- Turnaround
- 1-3 business days
- Availability
- Our partner lab does not serve ND, RI, NY, NJ, MD or HI. Confirm availability for your location with the collection lab.
Before you go
- Order your test before visiting a lab, then use the requisition form in your account.
- Print the requisition form, or fax it to the lab directly from your account.
- No scheduling is needed — visit the collection lab during its normal business hours.
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Bring a government-issued photo ID in case the lab requests it.
- Results are posted to your secure account within 1–3 business days.
Requirements are summarized from our partner lab's published policies. Preparation and availability can change — confirm current instructions with the collection lab before your visit.
What this test is
This test involves drinking a lactose-containing solution and then having blood samples taken at timed intervals. It measures changes in blood glucose and may also track symptoms, because lactose normally breaks down into simpler sugars that raise glucose. A clinician uses the pattern to help evaluate possible lactose intolerance.
What it measures
- Fasting blood glucose — starting glucose level before the lactose drink
- Blood glucose after lactose — timed glucose readings after drinking the lactose solution
- Change in blood glucose — rise or lack of rise compared with the fasting level
- Symptoms during test — bloating, gas, cramping, or diarrhea reported after the drink
What the test involves
You drink a measured lactose solution after a fasting period, and a healthcare professional collects blood samples at set times afterward. The samples are usually drawn from a vein in the arm with a standard blood draw.
Why it is often ordered
A clinician may order this test when someone reports bloating, gas, diarrhea, or cramping after consuming dairy products. It can help distinguish lactose intolerance from other digestive issues and guide further discussion.
Preparation
The collection lab will provide specific instructions, which often include fasting for a certain number of hours before the test. Follow those instructions exactly, and ask the lab about any medications or foods to avoid.
How results are reported
Results are typically reported as blood glucose levels at each time point along with any symptoms observed during the test. Reference ranges and interpretation vary by laboratory, so the ordering clinician reviews the pattern in context.
Before you go
- Whether fasting is required and for how long
- Which medications or supplements may affect the test
- Whether symptoms during the test should be recorded and shared
Cities
Lactose Tolerance Test in Illinois communities
Choose your city for local context and to order this test.