Sure, it’s ok to use the extract instead of capsules, in fact, I’d say it’s better. Just be sure to follow the instructions as far as how to mix the drops with water, etc.
What foods are you speaking of as far as the wholegrain oats?
Non-glutinous grains such as quinoa, buckwheat, rice bran and oat bran are allowed on some of the Candida diets, however, I’ve just started adding these to my diet after many months.
I’d say, anything of question that you wish to add to your diet, test it very slowly, just a few bites to start with so that you don’t cause any unnecessary reactions.
Good luck to you.