Blood Test for Lactose Intolerance?

It's my understanding that an allergy to milk and lactose intolerance are different things. Is that right? Correct, there are two separate things that people sometimes refer to as "lactose intolerance"! You may want to clarify with your doctor which of these was actually tested for. One is actual lactose intolerance, where your body stops producing lactase (the enzyme that breaks down lactose into simpler sugars glucose and galactose). Since you can't digest it, the bacteria in your gut are happy to do so and cause gastric distress as a side effect. It's very common in adults. The other condition is casein allergy, which is a genuine allergy to a protein in milk. You can try taking over-the-counter lactase tablets (the 60-pack at Target is the most inexpensive that I've found) with any food that contains milk for a week or so and see if it helps your stomach issues. I did this when I started having ridiculous afternoon bloating a couple years ago, and the tablets did end up helping.

Also try liquid lactase. You put it in milk, cream, yogurt etc then wait 10 hours and consume normally. It doesn't affect the taste for anyone else (nor harm them) but it'll make your life a lot easier. Here in the UK it's £12 for enough drops to handle 70 pints. Way cheaper than buying the lactose free stuff - which if you read the ingredients just includes liquid lactase! If you put it in things you are warming up (like custard) then it only needs 10 minutes.

Everyone I know who has determined that they were lactose intolerant (including myself) has just abstained from dairy for a few weeks to determine if that's indeed the problem. If your problems subside, you've found the culprit. Fortunately for most people it's a pretty easy fix - just take a Lactaid pill every time you consume dairy. I've been lactose intolerant for 20+ years and taking the Lactaids is second nature.

I'm not the type of doctor who ever does testing for lactose intolerance, but I was curious, so I looked up the workup for it on my favorite free online medical resource, eMedicine. Their article says that the test you linked to, the one with the serial blood glucose level measurement, is rarely used in regular practice, and the breath hydrogen test is the test of choice. However, the same section also suggests a simple elimination diet as a test of lactose intolerance as well, as radioamy suggests. "http://emedicine.medscape.com/article/187249-workup#a0721." And it's free!

My GI doc is currently administering a series of hydrogen breath tests. I took the lactose test this week, which consisted of a day-before prep limiting food, beverages limited to water, a 12 hour overnight fast, ingesting lactose (not too bad) and then three hours of intermittent breathing into "balloons" which will be sent out for evaluation. No blood draws. Same test, 1.5 hours, was administered for SIBO last week; and, upcoming is another 3 hour test for fructose. Being thorough, assessing persistent right quadrant pain. A few months ago, my endocrinologist did a CLA Allergen -Specific IgE assay (bloodwork), among which was milk, and my Class for that was 1/0 (very low - very high= 4). I'm assuming that this will be more thorough.

My mom was diagnosed lactose intolerant when she was in her 20s. My sister was diagnosed through the test where she had to drink a cup full of lactose. So, when I started having problems, I was "diagnosed" based on family history. So, I started using the same supplements that my mom and sister were using and things got better. I use the Lactase Enzyme pills from Vitamin World. It's $6 a bottle but they go on sale fairly often.

Thanks for the answers everybody! The reason I was interested in being tested for lactose intolerance is that taking dairy out of my diet definitely improves my symptoms but the lactase pills don't seem to do anything. I will give liquid lactase a try and maybe a different brand of the pills.