I had severe lactose intolerance after surgery and I didn't before surgery. I was even unable to drink Lactaid milk. So I switched to Light Soy milk and used Unjury protein powder without problems. When I did this, each shake was about 28 grams of protein for 8oz of fluid. At about a month out, I was able to tolerate EAS Carb Advatedge ready to drink shakes. Now that I am 6 months out, I am ever so slowly introducing milk products back. Plain cow's milk still causes me a little problem, but its better...most other milk products are back on the menu. It just took that long for my stomach to produce the enzyme, lactase, again. Tell him it gets better. The first month for me was hellish. It's difficult to make your plans if you don't know if you going to have the screaming diarrhea from hell that knocks buzzards off of gut wagons....in public much less in your own home. I made sure I was always within a 5 second walking distance of a toilet and had flushable wipes on my person at all times. I get it...believe me..I get it. But...it does get better. Good luck! Try the plain soy milk for awhile...and then slowly introduce milk when you are a couple of months out. Remember...I am 6 months out and just now have started eating Greek yogurt without issue. If I had tried that at even 3 moths out, it wouldn't have been pretty!