I like to drink smoothies for breakfast, but i need protein. when i drink whey protein it causes abdominal pain. what else could i use?

Drink a lot of fluid: When you use the whey protein to try and decrease the abdominal pain. The best sources of protein are from regular food instead of supplements. Try some greek yogurt in your smoothie. Maybe add eggs or cottage cheese into your breakfast routine.

Protein Powders: Whey is a good protein source, but it's not for you if you're intolerant to it. You could use soy or pea protein powder instead. Coconut milk is a nice addition, with ground flax seeds and frozen berries. You could also add some almond butter if you want.